A woman leaves flowers in front of the Carabinieri station where Mario Cerciello Rega was based, in Rome. Picture: Andrew Medichini/AP

Rome — Italian police said Saturday that two 19-year-old American tourists have confessed in the fatal stabbing of an Italian paramilitary policeman who was investigating the theft of a bag.

In a statement, Carabinieri officers investigating the death early Friday of officer Mario Cerciello Rega, 35, said the American men were detained for alleged murder and attempted extortion after being questioned overnight. They were taken to a Rome jail as the investigation continues. Italian authorities have not released their names.

The two had snatched the bag of a drug dealer in Rome after the man apparently gave them "a different substance" instead of cocaine, according to an Italian investigator who spoke on condition of anonymity since the probe was ongoing.

The Carabinieri said the Americans demanded a 100-euro ($112) ransom and a gram of cocaine to return the bag. The alleged dealer called police, saying he had arranged a meeting with the thieves to get his bag and cellphone back. Police says there was a scuffle at the rendezvous site and the policeman was stabbed eight times, dying shortly afterward in the hospital.

Officer Mario Cerciello Rega, 35, who was stabbed to death in Rome. Picture: Italian Carabinieri/AP

The Carabinieri said video surveillance cameras and witnesses allowed them to quickly identify the two Americans and find them in a hotel near the scene of the slaying. Police said the two Americans were "ready to leave" Italy when they were found.

A woman leaves a note in memory on the spot where Mario Cerciello Rega was stabbed to death in Rome Picture: Andrew Medichini/AP

In a search of their hotel room, the Carabinieri said they found a long knife, possibly the one used to attack Cerciello Rega. Police said the knife had been hidden behind a panel in the room's ceiling. Police also said they found clothes the two apparently were wearing during the attack.

People stop by flowers and messages left on the spot in Rome where Carabinieri officer Mario Cerciello Rega was stabbed to death. Picture: Angelo Carconi/ANSA via AP

The Carabinieri statement said the two Americans admitted responsibility after being questioned by prosecutors and faced with "hard evidence."

It was not known if the Americans had an Italian lawyer.

Carabinieri Lt. Col. Orazio Ianniello said Saturday the suspects weren't being immediately named because they have no criminal records.

AP