CHESTER, S.C. - Chester County Sheriff Alex Underwood has been sued by a deputy who said he coerced her into having sex with him and then passed her over for a promotion.

The lawsuit, filed last week, is the latest in a series of disputes the sheriff has faced since he was elected in 2012. He denies all the allegations.

Sheriff's Capt. Mary Anne Tolbert sued Underwood. She said he coerced her into having sex several places across the county for nine months in 2013, including his home he shares with his wife and the home of the police chief in the city of Chester.

Tolbert had severe panic attacks in October and took two weeks of medical leave. When she returned, she told Underwood she would no longer have sex with him, and the sheriff began to criticize her work in front of others, according to the lawsuit.

Underwood also passed her over for the chief deputy job, even though she had been promised the position and already had experience supervising most of the divisions in the sheriff's office, according to court papers.

Underwood denies all the claims in the lawsuit.

"The allegations are completely false, and I look forward to vigorously defending them through trial, if necessary," the sheriff said in a statement to local media outlets. "I would love to comment on this, but I have been advised by my attorney not to do so at this time."

Tolbert has been on medical leave since April because of the severe stress and anxiety caused by Underwood's treatment, her lawsuit said. Tolbert's attorney would not say if his client has filed a criminal complaint against Underwood.

Underwood has had a rocky 19 months as sheriff. Since he took office, the County Council has tried to remove operation of the county's 911 service from Underwood, suing the sheriff when he would not relinquish control.

Underwood and a few of his deputies also got involved in a scuffle with firefighters at the scene of a wreck. Two firefighters were arrested, and the State Law Enforcement Division is investigating.