BANGOR — A residential care center employee in Maine is going to prison after pleading guilty to what prosecutors described as “grotesque and pervasive” assaults on a disabled man.

Zachery Conners, 26, was among four workers accused of abuse including waterboarding, choking and sexually assaulting a nonverbal adult male client at the Lee Residential Care center in Hampden.

He pleaded guilty to endangering the welfare of a dependent person over a three-year period and was sentenced on Aug. 30 to 2 ½ years in prison. His three former colleagues await trial on similar charges, according to court documents.

Prosecutors said the four workers had complete control over residents and used their power to commit torture and abuse. Conners was accused of choking the victim until he passed out and participating in waterboarding in which the victim’s face was covered with cloth while water was sprayed on his face to simulate drowning, prosecutors said.

The victim also was punched in the genitals, beaten with a large spoon, sexually violated with objects and encouraged to engage in a sex act with another resident, prosecutors said.

“The defendant was paid to protect these vulnerable citizens. He did the exact opposite,” Assistant Attorney General Patricia Poulin wrote.

Messages seeking comment Tuesday from the center and Conners’ lawyer were not immediately returned.

Lee Residential Services lost its state license last year after law enforcement investigations that began with a report of a staff member bringing a weapon to work in January 2022 and a report of abuse two months later, said Lindsay Hammes, spokesperson for the Maine Department of Health and Human Services.

She said the department fully supported and cooperated with the investigation “and is deeply disturbed by the information law enforcement uncovered.”