Military prosecutors plan to file murder, kidnapping and conspiracy charges against seven Marines and a Navy corpsman in the shooting death of an Iraqi man in April, a defense lawyer said Thursday.

The eight men are being held in the brig at Camp Pendleton Marine Corps base north of San Diego, said Jeremiah Sullivan III, who represents one of the men.

The Iraqi man reportedly was dragged from his home west of Baghdad and shot. Both the Los Angeles Times and NBC News said troops may have planted an AK-47 and shovel near the body to make it appear the man was an insurgent burying a roadside bomb.

CountryWatch: Iraq

Neither media outlet suggested a possible motive for the April 26 killing in Hamandiya.

The man's death was unrelated to the shootings of as many as two dozen civilians in the western Iraqi city of Haditha in November. The Pentagon is investigating troops from a different Marine regiment in that case.

The men being held at Camp Pendleton served in Iraq with the 3rd Battalion, 5th Marine Regiment, and are members of the battalion's Kilo Company. The highest-ranking among them is a staff sergeant.

Sullivan, a former Navy JAG who runs a civilian practice in San Diego, said he learned from Marine Corps attorneys that the charges have been drafted and official charging documents could be given to the men as early as Friday.

Separately, another group of five Marines in Kilo Company, including a lieutenant who commanded the platoon, are under investigation for injuring a suspect in their custody, according to a defense attorney who has been contacted by the family of one of the Marines. He spoke Thursday only on condition of anonymity because he has not taken on the case.

The Marine Corps and Pentagon spokesmen have refused to comment on any aspect of the Iraqi man's death since the investigation was announced May 24.

However, a Pentagon official said Thursday that charges are expected to be brought "very soon." The official, who spoke only on condition of anonymity because he is not authorized to discuss charges before they are filed, could not confirm the specific counts.

When the Pentagon announced it was investigating the death it provided no details about the incident other than to say that "several service members" from the 3rd Battalion, 5th Marine Regiment were suspected of involvement. The servicemen were "removed from operations" and sent back to the U.S. pending the results of the criminal investigation, it said.

Sullivan said the eight men are being held in solitary confinement.

"There's concern about the publicity of Haditha having a detrimental impact on the case," he said. "My concern is that the whole politics of this. There's an assumption that these guys are guilty before there's been an opportunity for a thorough, impartial investigation."

Under military law, after charges are served defendants have the right to an Article 32 hearing, the military equivalent of a civilian grand jury investigation.

An investigating officer presides over the hearing and makes a recommendation to the Marine general who directed the investigation. The general has the final say whether to order a court-martial and what charges, if any, the defendants will face.