KINGFISHER, Okla. (AP — A man was sentenced to life in prison after pleading guilty to killing four workers at an Oklahoma marijuana farm in 2022.

Chen Wu pleaded guilty at a court hearing Friday to four counts of first-degree murder and to one count of assault and battery with a deadly weapon in connection with the Nov. 20, 2022 killings, according to court records.

Prosecutors say Wu, also known as Wu Chen in jail records, fatally shot three men and a woman in a garage at the farm west of Hennessey, a town about 55 miles (90 kilometers) northwest of Oklahoma City.

As part of a plea agreement, Wu was sentenced to life in prison without parole for each of the murder counts and given a 20-year prison term for the assault charge. He will serve his sentences concurrently.

Wu, 47, was arrested in Florida two days after the shooting and was later extradited to Oklahoma.

In court records, prosecutors had alleged Wu had demanded the return of his $300,000 investment in the marijuana operation shortly before he shot the victims.

Killed in the attack were Quirong Lin, Chen He Chun, Chen He Qiang and Fang Hui Lee, court documents show. A fifth person, Yi Fei Lin, was wounded. Authorities later charged Yi Fei Lin with a separate assault charge. That case remains pending.

Authorities have said Wu and all of the victims were Chinese citizens and that the pot farm on a 10-acre (4-hectare) farm was operating under an illegally obtained license to grow marijuana for medical purposes.

“This case should serve as a reminder of the dangers surrounding illegal marijuana activity in Oklahoma,” said Kingfisher County District Attorney Tommy Humphries, according to The Oklahoman.