Injured people are carried out of a shopping mall after a shooting in Alpen aan den Rijn, 25 kilometers southwest of Amsterdam, Netherlands. A gunman opened fire with an automatic weapon at a crowded shopping mall, leaving at least six people dead and wounding 11 others. The attacker was among the dead after fatally shooting himself. Photo: AP
Injured people are carried out of a shopping mall after a shooting in Alpen aan den Rijn, 25 kilometers southwest of Amsterdam, Netherlands. A gunman opened fire with an automatic weapon at a crowded shopping mall, leaving at least six people dead and wounding 11 others. The attacker was among the dead after fatally shooting himself. Photo: AP
A woman is comforted after a shooting at a shopping mall in Alphen aan den Rijn, Southern Netherlands. A gunman opened fire with an automatic weapon at a crowded shopping mall, leaving at least six people dead and wounding 11 others. The attacker was among the dead after fatally shooting himself. Photo: Reuters
A woman is comforted after a shooting at a shopping mall in Alphen aan den Rijn, Southern Netherlands. A gunman opened fire with an automatic weapon at a crowded shopping mall, leaving at least six people dead and wounding 11 others. The attacker was among the dead after fatally shooting himself. Photo: Reuters
Police officers and neighbors are seen near Ridderhof shopping mall in Alphen aan den Rijn, 25 kilometers southwest of Amsterdam, Netherlands. A gunman opened fire with an automatic weapon at a crowded shopping mall, leaving at least six people dead and wounding 11 others. The attacker was among the dead after fatally shooting himself. Photo: AP
Police officers and neighbors are seen near Ridderhof shopping mall in Alphen aan den Rijn, 25 kilometers southwest of Amsterdam, Netherlands. A gunman opened fire with an automatic weapon at a crowded shopping mall, leaving at least six people dead and wounding 11 others. The attacker was among the dead after fatally shooting himself. Photo: AP
A body is covered in foil after a shooting at a shopping mall in Alphen aan den Rijn, Southern Netherlands. A gunman opened fire with an automatic weapon at a crowded shopping mall, leaving at least six people dead and wounding 11 others. The attacker was among the dead after fatally shooting himself. Photo: Reuters
A body is covered in foil after a shooting at a shopping mall in Alphen aan den Rijn, Southern Netherlands. A gunman opened fire with an automatic weapon at a crowded shopping mall, leaving at least six people dead and wounding 11 others. The attacker was among the dead after fatally shooting himself. Photo: Reuters
Police cordon off the scene of a shooting at a shopping mall in Alphen aan den Rijn, Southern Netherlands. A gunman opened fire with an automatic weapon at a crowded shopping mall, leaving at least six people dead and wounding 11 others. The attacker was among the dead after fatally shooting himself. Photo: Reuters
Police cordon off the scene of a shooting at a shopping mall in Alphen aan den Rijn, Southern Netherlands. A gunman opened fire with an automatic weapon at a crowded shopping mall, leaving at least six people dead and wounding 11 others. The attacker was among the dead after fatally shooting himself. Photo: Reuters
Police cordon off the scene of a shooting at a shopping mall as people are evacuated from the scene in Alphen aan den Rijn, Southern Netherlands. A gunman opened fire with an automatic weapon at a crowded shopping mall, leaving at least six people dead and wounding 11 others. The attacker was among the dead after fatally shooting himself. Photo: Reuters
Police cordon off the scene of a shooting at a shopping mall as people are evacuated from the scene in Alphen aan den Rijn, Southern Netherlands. A gunman opened fire with an automatic weapon at a crowded shopping mall, leaving at least six people dead and wounding 11 others. The attacker was among the dead after fatally shooting himself. Photo: Reuters
An injured person is carried out of a shopping mall by an ambulance crew and emergency workers after a shooting in Alpen aan den Rijn, 25 kilometers southwest of Amsterdam, Netherlands. A gunman opened fire with an automatic weapon at a crowded shopping mall, leaving at least six people dead and wounding 11 others. The attacker was among the dead after fatally shooting himself. Photo: AP
An injured person is carried out of a shopping mall by an ambulance crew and emergency workers after a shooting in Alpen aan den Rijn, 25 kilometers southwest of Amsterdam, Netherlands. A gunman opened fire with an automatic weapon at a crowded shopping mall, leaving at least six people dead and wounding 11 others. The attacker was among the dead after fatally shooting himself. Photo: AP
Injured people are carried out of a shopping mall after a shooting in Alpen aan den Rijn, 25 kilometers southwest of Amsterdam, Netherlands. A gunman opened fire with an automatic weapon at a crowded shopping mall, leaving at least six people dead and wounding 11 others. The attacker was among the dead after fatally shooting himself. Photo: AP
Injured people are carried out of a shopping mall after a shooting in Alpen aan den Rijn, 25 kilometers southwest of Amsterdam, Netherlands. A gunman opened fire with an automatic weapon at a crowded shopping mall, leaving at least six people dead and wounding 11 others. The attacker was among the dead after fatally shooting himself. Photo: AP
Police cordon off the scene of a shooting at a shopping mall in Alphen aan den Rijn, Southern Netherlands. A gunman opened fire with an automatic weapon at a crowded shopping mall, leaving at least six people dead and wounding 11 others. The attacker was among the dead after fatally shooting himself. Photo: Reuters
Police cordon off the scene of a shooting at a shopping mall in Alphen aan den Rijn, Southern Netherlands. A gunman opened fire with an automatic weapon at a crowded shopping mall, leaving at least six people dead and wounding 11 others. The attacker was among the dead after fatally shooting himself. Photo: Reuters
A police man in a bomb disposal suit checks the scene of a shooting at a shopping mall in Alphen aan den Rijn, Southern Netherlands. A gunman opened fire with an automatic weapon at a crowded shopping mall, leaving at least six people dead and wounding 11 others. The attacker was among the dead after fatally shooting himself. Photo: Reuters
A police man in a bomb disposal suit checks the scene of a shooting at a shopping mall in Alphen aan den Rijn, Southern Netherlands. A gunman opened fire with an automatic weapon at a crowded shopping mall, leaving at least six people dead and wounding 11 others. The attacker was among the dead after fatally shooting himself. Photo: Reuters
Injured people are carried into an ambulances after a shooting in Alpen aan den Rijn, 25 kilometers southwest of Amsterdam, Netherlands. A gunman opened fire with an automatic weapon at a crowded shopping mall, leaving at least six people dead and wounding 11 others. The attacker was among the dead after fatally shooting himself. Photo: AP
Injured people are carried into an ambulances after a shooting in Alpen aan den Rijn, 25 kilometers southwest of Amsterdam, Netherlands. A gunman opened fire with an automatic weapon at a crowded shopping mall, leaving at least six people dead and wounding 11 others. The attacker was among the dead after fatally shooting himself. Photo: AP
Police cordon off the scene of a shooting at a shopping mall as people are evacuated from the scene in Alphen aan den Rijn, Southern Netherlands. A gunman opened fire with an automatic weapon at a crowded shopping mall, leaving at least six people dead and wounding 11 others. The attacker was among the dead after fatally shooting himself. Photo: Reuters
Police cordon off the scene of a shooting at a shopping mall as people are evacuated from the scene in Alphen aan den Rijn, Southern Netherlands. A gunman opened fire with an automatic weapon at a crowded shopping mall, leaving at least six people dead and wounding 11 others. The attacker was among the dead after fatally shooting himself. Photo: Reuters
Police cordon off the scene of a shooting at a shopping mall in Alphen aan den Rijn, Southern Netherlands. A gunman opened fire with an automatic weapon at a crowded shopping mall, leaving at least six people dead and wounding 11 others. The attacker was among the dead after fatally shooting himself. Photo: Reuters
Police cordon off the scene of a shooting at a shopping mall in Alphen aan den Rijn, Southern Netherlands. A gunman opened fire with an automatic weapon at a crowded shopping mall, leaving at least six people dead and wounding 11 others. The attacker was among the dead after fatally shooting himself. Photo: Reuters
Injured people are carried out of a shopping mall after a shooting in Alphen aan den Rijn, 15 miles (25 kilometers) southwest of Amsterdam, Netherlands. A gunman opened fire with an automatic weapon at a crowded shopping mall, leaving at least six people dead and wounding 11 others. The attacker was among the dead after fatally shooting himself. Photo: AP
Injured people are carried out of a shopping mall after a shooting in Alphen aan den Rijn, 15 miles (25 kilometers) southwest of Amsterdam, Netherlands. A gunman opened fire with an automatic weapon at a crowded shopping mall, leaving at least six people dead and wounding 11 others. The attacker was among the dead after fatally shooting himself. Photo: AP
Police officers and an ambulance outside a shopping mall after a shooting in Alpen aan den Rijn, 25 kilometers southwest of Amsterdam, Netherlands. A gunman opened fire with an automatic weapon at a crowded shopping mall, leaving at least six people dead and wounding 11 others. The attacker was among the dead after fatally shooting himself. Photo: AP
Police officers and an ambulance outside a shopping mall after a shooting in Alpen aan den Rijn, 25 kilometers southwest of Amsterdam, Netherlands. A gunman opened fire with an automatic weapon at a crowded shopping mall, leaving at least six people dead and wounding 11 others. The attacker was among the dead after fatally shooting himself. Photo: AP
A police man attends to a person who witnessed a shooting at a shopping mall in Alphen aan den Rijn, Southern Netherlands. A gunman opened fire with an automatic weapon at a crowded shopping mall, leaving at least six people dead and wounding 11 others. The attacker was among the dead after fatally shooting himself. Photo: Reuters
A police man attends to a person who witnessed a shooting at a shopping mall in Alphen aan den Rijn, Southern Netherlands. A gunman opened fire with an automatic weapon at a crowded shopping mall, leaving at least six people dead and wounding 11 others. The attacker was among the dead after fatally shooting himself. Photo: Reuters

Church services were held in a quiet suburb outside Amsterdam to mourn six people killed by a gunman at a crowded mall, as investigators puzzled over his motive and struggled to explain how he was able to obtain and legally own five firearms in the Netherlands. The attacker, identified as 24-year-old Tristan van der Vlis, had minor run-ins with the police, including an illegal weapons possession charge in 2003 when he was 17 that was eventually dropped. Van der Vlis opened fire in Alphen aan den Rijn with what witnesses described as a machine gun on one of the first pleasant Saturdays of spring, authorities said. In addition to the fatalities, he wounded 15 others, including an infant, before fatally shooting himself in the head at the Ridderhof mall.

Three of the wounded remained in critical condition. The infant was among two people slightly wounded, but was under observation at a hospital. Authorities refused to say whether any other children were killed or wounded in the attack and they haven't released a list with the identities of the victims, citing privacy reasons.