OAKLAND (CBS SF / AP) — Prosecutors say owners of mango-themed Chinese-Malaysian restaurants in the Bay Area must pay their workers more than $1 million in wage-theft restitution.

Alameda County District Attorney Nancy E. O’Malley said Thursday that Hai Jie Chen and Hak Chun Ng were sentenced this week and placed on probation.

They owe back wages to 56 restaurant workers at Mango Garden in Fremont, Mango Jungle in San Jose and Mango Blaze in San Mateo.

An investigation found that the victims worked up to 12 hours a day, six days a week, for as little as $2 dollars an hour. The workers were denied overtime pay and some were denied medical treatment.

Chen was convicted of felony violations of wage theft conspiracy, and tax and insurance fraud. Ng was convicted of a misdemeanor violation of failing to pay minimum wage.

© Copyright 2019 CBS Broadcasting Inc. All Rights Reserved. The Associated Press contributed to this report.