ROME — Two American teens have confessed to the fatal stabbing of an Italian police officer in Rome, which occurred in the early hours of Friday.

The alleged murderer, 19-year-old Elder Finnegan Lee, and his accomplice, 18-year-old Christian Gabriel Natale Hjorth, were arrested shortly after the death of 35-year-old deputy sergeant Mario Cerciello Rega of the Carabinieri military police, and have been charged with aggravated homicide and attempted extortion.

According to a reconstruction of events by Italian media, the young men purchased what they believed to be cocaine from a drug dealer named Sergio Brugiatelli in the Trastevere district of Rome, only to find later that the powder was actually just ground aspirin.

A surveillance video caught the two returning to the square where they had bought the fake cocaine, where they proceeded to steal the Brugiatelli’s backpack. When the dealer called his cellphone, which was still inside the bag, the teens demanded 100 euros along with one gram of real cocaine in exchange for the backpack and its contents.

Brugiatelli, who is allegedly a police informant, called the police and invited them to be present at the meeting. When the youths arrived, officer Rega approached them together with his partner officer Andrea Varriale, both in plain clothes, and they identified themselves as police and attempted to question the teens about the drug deal. Lee reportedly then punched and kicked officer Rega and then stabbed him eight times with a large knife, while Christian Hjorth held back officer Varriale, preventing him from intervening to assist Rega.

Rega, who had just returned to duty from his honeymoon days earlier, died in the emergency room of the Santo Spirito hospital a few hours later.

“I didn’t think he was a policeman and I was afraid of being cheated again,” said Lee during Friday’s long interrogation. He also said he had brought along the knife for fear of meeting dangerous individuals.

In a statement on Saturday morning, police said that they had interrogated the two youths under the direction of the local Rome prosecutor.

“In the face of overwhelming evidence, they confessed to the charges,” the statement said, adding that the basic facts of the assault were backed up by the testimony of numerous witnesses.

The arrest warrant describes the multiple stabbing as a disproportionate reaction since officers Varriale and Rega had not drawn their weapons.

Police said they have discovered “numerous objects of investigative interest” both in the hotel room, where the murder weapon was found hidden behind a ceiling panel, and in the vicinity of the crime scene, where the stolen backpack was found stuffed in a flower box.

Investigators also have recovered the youths’ cellphones as well as the surveillance footage from the cameras that recorded them in in the square where the theft took place, and in the hotel where the two are seen entering and exiting before and after the time of the murder.

The two youths had already packed their bags to leave the hotel and planned to depart from Rome on a flight to the United States later on Friday.

For his part, Officer Rega has been described as an exemplary citizen. He reportedly did volunteer work with the poor, accompanied sick people to Catholic shrines, and brought meals to the homeless.

His funeral on Monday will be held at the same church where he was married 43 days ago.

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