Police have identified through DNA test results that a man who died last month after confessing he was the fugitive wanted for one of a series of terrorist bombings in 1970s Japan was the suspect, an investigative source said Tuesday.

The man admitted to being the alleged bomber Satoshi Kirishima, 70, who had been a member of the extreme left-wing group East Asia Anti-Japan Armed Front, a few days before he died of illness at a hospital.

Screenshot taken from the website of the Tokyo Metropolitan Police Department shows Satoshi Kirishima. (Kyodo)

Suspecting Kirishima's involvement in four additional bombing incidents that occurred in 1975, police referred all five cases to prosecutors Tuesday on alleged violation of the explosives control act and suspicion of attempted murder, the source said.

DNA tests conducted on the man and his relatives have shown that "there is no inconsistency in kinship" between the two parties.

Kirishima had long been wanted on suspicion that he planted and detonated a homemade bomb in a building in Tokyo's Ginza district on April 19, 1975. He was placed on a nationwide wanted list the following month.

Police will continue to investigate how he managed to evade them for 49 years as a fugitive and whether anyone helped him survive while on the run.

He had been living under the name Hiroshi Uchida and was an employee of a building firm in Fujisawa in Kanagawa Prefecture near Tokyo for around 40 years.

He denied his involvement in the incident that led him to be on the wanted list when he was interviewed by police at the hospital, but hinted at taking part in other bombing incidents targeting a construction firm, investigative sources have said.

He also told police that he had been alone and on the run without any help from supporters and that he regretted his involvement in the bombings, according to the sources.

Kirishima had been making outpatient visits to the hospital in Kamakura, Kanagawa Prefecture for about a year and was hospitalized in January. He confessed to being Kirishima four days before his death on Jan. 29 after undergoing treatment for terminal stomach cancer.

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