A member of a disbanded Japanese left-wing militant group has been sentenced to 12 years in prison for a mortar attack on the Japanese Embassy in Indonesia in 1986.

Japanese media report that a Tokyo court handed down the sentence Thursday against former Japanese Red Army member Tsutomu Shirosaki (tsoo-toh-moo shee-roh-sah-kee).

He was accused of conspiring with another person to fire two rounds at the embassy from a hotel room in Jakarta, the capital of Indonesia. Neither exploded.

The 68-year-old Shirosaki was imprisoned in the United States for a rocket attack on the U.S. Embassy in Jakarta the same year. He was released in 2015, and re-arrested upon his return to Japan.

The Japanese Red Army carried out a series of violent hijackings and attacks in the 1970s and 1980s.