A U.S. Marine accused of raping a 14-year-old Japanese girl was convicted of a lesser charge Friday during a court martial and sentenced to four years in prison in a case that inflamed public anger at the American military presence on Okinawa.

Staff Sgt. Tyrone L. Hadnott, 38, was found guilty of abusive sexual conduct, said Master Sgt. Chuck Albrecht. He said four other charges _ rape of a child under 16, making false official statements, adultery and "kidnapping through inveigling," or trickery _ were dropped.

Though Hadnott was sentenced to four years in prison, he will only serve a maximum of three years, with the fourth year of the sentence suspended under a pretrial agreement, the Marines said in a statement.

Japanese police apprehended Hadnott in February, but released him after the girl dropped charges. U.S. authorities then investigated the case under the strict military justice code.

Japan hosts some 50,000 American troops under a security treaty. About half of them are based on the tiny, congested island of Okinawa.

Hadnott's Feb. 11 arrest _ as well as a series of other damaging criminal accusations against American troops _ worsened resentment at the U.S. military presence on the southern island.

The incident prompted the U.S. military to severely restrict troop movements on Okinawa and elsewhere, and conduct an ongoing review of its anti-sexual assault education programs and guidelines.

Lt. Gen. Edward A. Rice, the commander of U.S. Forces Japan, told reporters Friday the military had completed a thorough review of anti-sexual assault guidelines and training.

"This is an example of we in the United States military will continue to hold our members accountable for their actions," Rice said of the Hadnott case. "He was found guilty and he will be held accountable for his actions."

Rice said that military anti-assault programs in Japan were found to be in compliance with Department of Defense rules.

Still, U.S. forces were taking additional measures such as integrating sexual assault awareness training into orientation programs for new arrivals and stepping up contacts with local businesses and other leaders to coordinate anti-crime efforts, Rice said.

"We're making a tremendous investment in trying to make sure we do everything we can to prevent even one crime from happening," he said.