Police officers leave a building connected to the Kudokai crime syndicate in western Japan, on September 15, 2014.

A district court in Japan on Tuesday sentenced the head of a gangster organization to death after its members killed one civilian and injured three others, although there was no direct evidence he ordered the attacks, public broadcaster NHK said.

In handing down the sentence, a judge at the court in Fukuoka, western Japan, said strict controls were in place at the Kudokai crime syndicate, and it was unthinkable that the attacks had been carried out without the leader’s authorization, NHK said.

Between 1998 and 2014, Kudokai members shot and killed a former head of a fishing cooperative, and injured three others including a nurse and a former police officer by shooting or stabbing, NHK said.

Defense lawyers for the Kudokai head, Satoru Nomura, 74, plan to appeal the ruling, Kyodo news agency said.