Tokyo police are questioning a man believed to be Satoshi Kirishima, a member of a militant group suspected in a series of bombings in Japan in the 1970s, The Asahi Shimbun learned on Jan. 26.

The National Police Agency has designated Kirishima, who would be 70 now, as a “wanted person of importance.”

In one of the attacks, Kirishima is believed to have planted and detonated a homemade bomb in a building in Tokyo’s Ginza district in April 1975. The explosion caused damage but no casualties.

Kirishima belonged to the East Asia Anti-Japan Armed Front, according to the Metropolitan Police Department.

His face has appeared on wanted posters nationwide. But for 49 years, police have been unable to locate him.

Tokyo police recently made contact with a person claiming to be Kirishima, and they are now trying to confirm his identity, sources said.

At least two other suspects in the group have fled Japan, police said.