Two American teenagers were jailed in Rome on Saturday as authorities investigate their alleged roles in the fatal stabbing of an Italian police officer on a street near their hotel.

A detention order issued by prosecutors was shown on Italian state broadcaster RAI, naming the suspects as Gabriel Christian Natale Hjorth and Finnegan Lee Elder. The order said they were both born in San Francisco, and according to the birth dates cited, Elder is 19 while Natale Hjorth turns 19 later this year.

Police in an earlier statement said the Americans are both 19.

In the detention order, Elder is described as repeatedly stabbing Carabinieri paramilitary police officer Mario Cerciello Rega, 35, several times on Friday. Investigators said Cerciello Rega, along with a fellow Carabinieri officer, were both in plainclothes when they confronted the two Americans in the wake of a drug deal gone wrong.

The other American was described in the document as pummeling Cerciello Rega's partner repeatedly with his bare hands. The partner, who was not seriously injured, has been described as a key witness in the investigation.

Under Italian law, persons participating in a killing, without actually carrying out the slaying itself, risk being charged also with murder.

Both suspects were also being investigated for attempted extortion connected to the alleged drug deal.

Elder's lawyer, Francesco Codini, told reporters that his client had exercised his right not to respond to questions during a detention hearing Saturday in the Rome jail where the two teens are being held.

Codini said he didn't want to say anything more out of "respect for the family" of the slain officer. Asked how Elder was doing psychologically, he replied with one word: "worn-out." Natale Hjorth's lawyer didn't speak to reporters waiting outside the jail after the hearing.

It wasn't known when the judge would rule on investigators' request to keep the suspects' jailed.

An Italian investigator who spoke on condition of anonymity since the probe was ongoing said that the pair had snatched the bag of a drug dealer in Rome after the man apparently gave them a different substance instead of the cocaine they were seeking.

In a statement, the Carabinieri contended that the Americans demanded a cash ransom and cocaine to return the knapsack.

They said the bag, with a phone inside, was snatched from an Italian man. The Americans in a phone call, the police contend, "threatened to not give it back to him without payment of 100 euros and a gram of cocaine."

Earlier, the Italian had been described as a drug pusher who allegedly swindled the Americans out of the cocaine they purportedly were seeking. But it wasn't immediately clear it the Italian was actually the pusher or somehow involved with him.

The victim of the bag-snatching later contacted Carabinieri after formally reporting the theft, and the plainclothes officers were sent to the site of the rendezvous to allegedly turn over the bag for ransom, the statement said.

The Americans, "even though the officers identified themselves as being Carabinieri, didn't hesitate to engage in a struggle, culminating in the mortal wounding" of the policeman, the statement said.

The officer died shortly afterward, in hospital.

The Carabinieri said video surveillance cameras and witnesses allowed them to quickly identify the 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, but didn't say where they planned to head.

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 dropped ceiling. Police also said they found clothes the two were wearing during the attack.

The Carabinieri statement said the two Americans, questioned by police under the direction of Rome prosecutors and confronted with "hard evidence," had "confessed to their blame."