Updated

Three American vigilantes tricked NATO peacekeepers (search) into helping with illegal raids, the security force said Wednesday, getting them to send explosives experts and bomb-sniffing dogs to check buildings in Kabul where they had detained suspects.

A spokesman said the men, led by former U.S. soldier Jonathan K. Idema (search), seemed authentic — fluent in military speak, decked out in faux U.S. Army fatigues and claiming to belong to a nonexistent task force.

"Their credibility was such that with their uniforms, their approach, our people believed they were what they said they were," said Cdr. Chris Henderson, a spokesman for the International Security Assistance Force (search). "It was a mistake."

Afghan officials said the three men, who were arrested July 5, could spend 20 years in jail on charges of hostage-taking and assault of Afghans allegedly found hanging upside down in their private jail.

It remained unclear if the three men had been picking up innocent Afghans of if they were trailing genuine militants plotting bombings or other violence.

Henderson said Idema called in bomb-disposal teams from the International Security Assistance Force to check houses and vehicles three times from June 20-24.

The teams found "traces" of explosives in two cases, and suspicious electronic components in a third, Henderson said. He wouldn't say whether they could have been used to make bombs.

Idema, formerly of Fayetteville, N.C., appeared in Afghanistan after the Sept. 11 attacks on the United States. He claimed in a book to have fought alongside the Northern Alliance troops who allied with U.S. forces to drive out the Taliban regime.

Better known as "Jack," he returned to Kabul some weeks ago with his partners. Police say he was armed and dressed in military gear and sometimes wore a flat woolen Afghan cap.

It remains unclear if Idema, who spent three years in a U.S. federal prison for a fraud conviction in the 1990s, was hoping to bank a million-dollar reward for information leading to the capture of Al Qaeda fugitives.

The U.S. military here insists that Idema, who has worked with several Western TV networks, has no connection with either it or the American government.

The U.S. Embassy has checked that the men are being treated properly, but there is no sign of an attempt to remove them from the country.

Fatah said the charges raised against the Americans, as well as four Afghans arrested along with them, carry jail terms of 16-20 years.

Abdul Baset Bakhtyari, a senior judge at Kabul's lower court, said it received the case Wednesday and it would be several days before a trial begins.

"It will be a public trial," Bakhtyari said. "They can bring lawyers from whichever country they want."

He said Idema and the two others would remain in Afghan custody.

Afghan officials say they freed all eight illegal prisoners, but residents in the Kabul neighborhood where one of the raids occurred say five men have not returned.

Henderson and an Afghan security official, who spoke on condition of anonymity, both said they didn't know if the five were now in Afghan custody.

Henderson insisted Wednesday that none of the peacekeepers had witnessed any abuse of detainees. "Had anyone in ISAF seen that, it would have been reported."

Defending the force's actions, he said Idema didn't seem out of the ordinary in Kabul, with its many armed Western operatives, from American spies to private security guards.

Still, when word of the operations reached higher officials a few days after the third raid, they became suspicious and contacted the U.S. military.

"At that point they said: 'this is Idema, he's not legitimate,"' Henderson said.

Armed with information from ISAF and the Americans, Afghan forces then raided Idema's jail in Kabul, he said.