Prosecutors demanded the death penalty Monday for a former Aum Shinrikyo member accused of taking part in the 1989 slaying of a Yokohama lawyer and his family.

Kazuaki Okazaki, 37, on trial before the Tokyo District Court, is the first cult defendant for which prosecutors have sought capital punishment in connection with the spate of crimes Aum's members stand accused of committing. Okazaki allegedly conspired with six other cult members, including Aum founder Shoko Asahara and the late cult science chief Hideo Murai, to kill anti-Aum lawyer Tsutsumi Sakamoto, 33, the lawyer's wife, Satoko, 29, and the couple's 1-year-old son, Tatsuhiko. He also is on trial for taking part in the lynching of errant cultist Shuji Taguchi in 1989.

The Sakamoto slayings are believed to have been perpetrated at the victims' Yokohama condominium early on Nov. 4, 1989. The trials of five others -- Asahara, Kiyohide Hayakawa, Tomomitsu Niimi, Tomomasa Nakagawa and Satoru Hashimoto -- are still in progress.