The leader of the Aum Shinrikyo cult, which carried out the deadly 1995 sarin gas attack on the Tokyo subway, has been executed, according to Japanese public broadcaster NHK.
Shoko Asahara, whose real name is Chizuo Matsumoto, had been in prison for 22 years before his execution this week. The attack left more than a dozen people dead and thousands injured.
Asahara’s death sentence was finalized in 2006, according to NHK, but trials of his co-conspirators dragged on for a further 12 years.
Twelve other members of Aum Shinrikyo were sentenced to death for their roles in the 1995 attack. It is unclear whether they were also executed this week.
Executions in Japan are carried out in secret, with no advance warning given to the prisoner, their family or legal representatives, according to Amnesty International. Prisoners often only learn out hours before that they are to be killed.
“These acts breach the right to life and the right to live free from torture,” Amnesty said in a recent report.