A high court on Thursday upheld a lower court ruling that found a prominent anti-U.S. military base activist in Okinawa guilty of several criminal offenses committed during protests in the island prefecture.

Hiroji Yamashiro, 66, a key figure in the movement against the relocation of the U.S. Marine Corps' Air Station Futenma within Okinawa, was given a two-year jail term, suspended for three years, in March for obstructing base transfer work and other acts.

Yamashiro, who is the head of the Okinawa Peace Action Center, was seeking to overturn the Naha District Court ruling, but the Naha branch of the Fukuoka High Court rejected his appeal.