Two Americans jailed for allegedly driving a group of would-be soldiers during a protest demanding the restoration of Haiti's army face up to three years in prison if convicted on conspiracy charges, a prosecutor said Monday.

Prosecutor Jean-Renel Senatus said in his office at the courthouse that one of the Americans, Jason William Petrie, was of concern because he had confessed in jail to having ties to criminal gangs.

"He has a lot of information he can give us," Senatus told The Associated Press.

Petrie, 39, of Barberton, Ohio, and Steven Parker Shaw, 57, of Dighton, Massachusetts, were charged with conspiracy after police arrested them for driving hopeful soldiers at the demonstration in Haiti's capital Friday that drew hundreds of participants.

Petrie has been coming to Haiti for 20 years and worked as an interpreter for foreigners. He has also been involved in Haitian politics, supporting losing presidential candidate Charles Henri-Baker in the 2010 election.

Petrie told the AP while in jail that he was friends with leaders of the pro-army group and was merely helping them. Shaw said he was lending a hand to Petrie.

Led by a band of former sergeants, marchers used a national holiday Friday to pressure President Michel Martelly to honor his campaign promise to reinstate the army, which was abolished in 1995 because of its involvement in coups and other abuses.

The demonstration began peacefully but protesters then threw rocks at United Nations peacekeepers near the National Palace. Police exchanged gunfire with others outside one of the old military bases that the pro-army group had taken over.

Police jailed a total of 53 people on a variety of charges, including possession of illegal weapons and not having paperwork for driving motorcycles, Senatus said. Those found with weapons face charges of "plotting against the internal security of the state," he said.

The arrests came as police emptied several former military bases and other public facilities that the lightly armed pro-army men had occupied since February. The former soldiers opened training camps and recruited young men and women hoping they could obtain a military job in a country where the bulk of the population lives on less than $2 a day.

One of the band's leaders, a former sergeant, was arrested on an assault charge. But about a half dozen other leaders went into hiding Saturday and have shut off their cellphones.