The lawyer of one of the U.S. Army reservists accused of abusing Iraqi detainees at Abu Ghraib (search) prison said Tuesday that military prosecutors have agreed to drop some of their charges after the soldier agreed to plead guilty to the rest.

Staff Sgt. Ivan L. "Chip" Frederick (search ) did not enter a plea when he went before a military judge in Mannheim during a pretrial hearing Tuesday.

But his lawyer, Gary Myers, told reporters afterward that Frederick would plead guilty to some charges against him at an Oct. 20 sentencing hearing in Baghdad. He would not say which charges.

"An agreement has been reached," Myers said. "Some of the initial charges have been dismissed, some remain. (To) Those that remain, Staff Sgt Frederick will plead guilty."

"He's taking responsibility for certain acts," Myers said. The lawyer refused to elaborate or to say whether his client would spend time in prison.

Frederick is charged with maltreating detainees, conspiracy to maltreat detainees, dereliction of duty and wrongfully committing an indecent act. He issued a statement Monday saying he would plead guilty to some offenses.

Military prosecutors were not immediately available for comment.