NEW YORK (KTRK) -- A man who used a meat cleaver to butcher five of his relatives, including four children under 10, was sentenced Tuesday to 125 years to life in prison.
Mingdong Chen had pleaded guilty to murder and manslaughter charges under a plea deal accepted on the condition that he "be incarcerated until the day he dies," State Supreme Court Justice Vincent Del Giudice said.
Chen was sentenced to three terms of 25 years to life for murder and two terms of 25 years to life for manslaughter.
"This defendant's vicious and sadistic attack makes him completely unfit to remain in society, and he will now spend the rest of his life behind bars," said Brooklyn District Attorney Ken Thompson.
A lawyer for Chen, 27, declined to comment.
Authorities say the Chinese immigrant confessed in Mandarin to killing his cousin's wife, 37-year-old Qiao Zhen Li, and her children, 9-year-old Linda, 7-year-old Amy, 5-year-old Kevin and 1-year-old William Zhou, in October 2013.
He was envious of his relatives' success and had been fired from restaurant jobs, according to authorities and his relatives.
Li called her mother-in-law in China on the night of Oct. 27, 2013, to say Chen was threatening her family with a knife, prosecutors have said. The mother-in-law then called other relatives in New York after hearing children crying in the background, they said.
By the time relatives and investigators arrived, Chen had slit the victims' throats and was dripping in blood, according to authorities.
Prosecutors said it remains a mystery exactly why Chen killed his family members.
"While we will never know what drove him to commit these murders, I hope that this sentence will offer this grieving family some measure of comfort," Thompson said.
Man who killed 5 relatives with meat cleaver gets 125 years