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.