Tokyo” Japan on Thursday hanged a Chinese man convicted of the murder of a family of four whose bodies were found handcuffed and weighted down with dumbbells in a bay, the justice minister said.

Masako Mori said she ordered the execution of Wei Wei “after careful consideration”, over robbery and multiple murders carried out with two other students in 2003.

Wei, a 40-year-old former language student in Japan, had pleaded guilty to the four murder counts but had contended he was not a central figure in the case.

The trio, reportedly allured by money, robbed the home of Japanese businessman Shinjiro Matsumoto, 41, in southwestern city of Fukuoka in June 2003 and strangled him with a tie.

His 40-year-old wife Chika was drowned in a bathtub and the children strangled or smothered.

The victims’ bodies were found dumped in Hakata Bay in Fukuoka, handcuffed and weighted down.

The other two suspects fled to China but were arrested there.

According to the Asahi Shimbun daily, the first execution of a foreigner since the ministry began announcing the names of those executed was in 2009.

A Chinese man was hanged for killing three Chinese whom he lived with near Tokyo and for injuring three, the Asahi said.

The execution is the second this year after Japan hanged two men convicted of murder in August.

With more than 100 inmates on death row, Japan is one of few developed nations to retain the death penalty, and public support for it remains high despite international criticism, including from rights groups.