Mingdong Chen pleaded guilty to murder of cousin’s wife and her four children and told police he was jealous of their success

This article is more than 4 years old

This article is more than 4 years old

A man who pleaded guilty to using a meat cleaver to kill five relatives, including four small children, has been sentenced to at least 125 years in prison.

Mingdong Chen, who had moved to the US from China, admitted that in October 2013 he killed his cousin’s wife, Qiao Zhen Li, 37, and her children, Linda, nine, Amy, seven, Kevin, five, and William Zhou, 18 months.

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The 27-year-old showed no visible reaction as he entered his plea on Wednesday. Under a deal with prosecutors Chen has a non-parole period of 125 years.

Prosecutors said Li called her mother-in-law in China on the evening of 27 October 2013 saying Chen was in the house with a knife and threatening the family. When the mother-in-law heard children crying in the background she called other relatives in New York who rushed to the home in Brooklyn’s Sunset Park. When they got there the five relatives were dead and Chen was dripping in blood.

Police said the family had been slaughtered, each of the five repeatedly stabbed and slashed in the throat and neck. Their bodies were found strewn about the house. Chen had been staying in their home for about a week before the killings.

When detectives questioned him Chen said he was jealous of the success of his fellow Chinese immigrants. Relatives said he had been fired from different restaurant jobs.

But exactly what set off Chen’s rampage remains a mystery.

“The question is why he’d do these things,” said the judge, Vincent Del Giudice, of the state supreme court. “It really doesn’t much matter.”

An assistant district attorney, Mark Hale, said prosecutors offered Chen a plea deal to spare Li’s husband and other relatives having “to relive the worst day of their lives”. Hale said they also wanted to ensure that Chen would publicly admit to the killings. Li’s husband was in court on Wednesday but did not comment.

In 2014 a Brooklyn judge ruled that Chen was not competent to stand trial because he had exhibited signs of mental illness that made him incapable of being able to assist in his own defence.

Chen’s attorney, Danielle Eaddy, declined to comment.