After 45 years on the run, a suspected ultra-leftist wanted for the 1971 killing of a police officer during a protest over the reversion of Okinawa to Japan may have been captured, investigative sources said.

Masaaki Osaka, 67, is suspected of involvement in an incident in which students assaulted a police box in Tokyo's Shibuya district using Molotov cocktails and iron bars on Nov. 14, 1971, as part of demonstrations against a Japan-U.S. agreement on the reversion of Okinawa. One officer died and three others were wounded.

A key member of the Japan Revolutionary Communist League National Committee — known commonly as Chukaku-ha (Middle Core Faction) and established in 1963 — Osaka has been at large since 1972.