Amnesty International criticized Japan on Friday for executing the founder of AUM Shinrikyo and six of its former members, saying capital punishment does not deliver justice for the victims of crimes committed by the doomsday cult.

"Justice demands accountability but also respect for everyone's human rights. The death penalty can never deliver this as it is the ultimate denial of human rights," Hiroka Shoji, East Asia researcher at Amnesty International, said in a statement.

The seven people executed included AUM's "guru" Shoko Asahara, who had been convicted of masterminding the 1995 sarin gas attack on the Tokyo subway system and other crimes. The subway attack killed 13 people and left more than 6,200 others injured.

Shoji said the seven deserved to be punished for the "despicable" attacks but "the death penalty is never the answer."

According to the Justice Ministry, the number of people with finalized death sentence dropped to 117 after the executions of the seven people on Friday.

The 117 includes 82-year-old Iwao Hakamada, who filed an appeal with the Supreme Court in June to seek a retrial of his conviction in a 1966 quadruple murder.

After spending nearly half a century on death row, the former boxer was freed in 2014 by a district court, which ordered the reopening of the case and suspended his death sentence and his continued detention.

A high court on June 11 scrapped the decision to grant him a retrial, but maintained the suspension of his death sentence and detention.