State prosecutors dropped a rape charge against an elected district attorney in western Pennsylvania on Tuesday but added new felony charges of sexual assault and aggravated indecent assault.

Somerset County District Attorney Jeffrey Lynn Thomas waived a preliminary hearing that had been scheduled for Tuesday. Thomas, 36, is accused of attacking a woman in her Windber home last month.

Charges of indecent and simple assault and criminal trespassing remain pending, while a strangulation charge was changed from a misdemeanor to a felony. Charges of unlawful restraint and false imprisonment were also added, the prosecutor's office said.

"It really calls into question the quality of the witness' allegations," Thomas' defense lawyer Ryan Tutera said. "Because the very first time we go to court they're withdrawing the most serious charge, which is rape. What does that say?"

A statement released by the attorney general's office said the change in charges means Thomas' "criminal exposure is significantly increased," and noted the waiver avoided having the victim testify at a preliminary hearing about a month after the alleged attack.

The police affidavit said the woman told investigators Thomas repeatedly contacted her over several years to seek a sexual relationship and would routinely drive around her house.

Last month, he allegedly sent her a Snapchat message saying he would be at her home in minutes, and she replied telling him to stay away. Shortly afterward, he walked uninvited into her home with several beer cans and handed her one, police said.

She told him to leave and slapped him, police said. Thomas struck her face, causing her nose to bleed, then pulled down her top and undressed himself, according to the affidavit.

"During the assault, Thomas grabbed her by the neck making it hard to breath(e)," investigators alleged.

When she demanded he leave, he grabbed her by the hair and asked if she planned to contact police, investigators said, and he left when she said she would not.

Tutera said Thomas maintains he is innocent of all the charges.

"We knew this wasn't a rape and we look forward to defending the rest of the case," he said.

Somerset County officials have said Thomas' access to his office and the courthouse are restricted, and Thomas has said he is taking a leave of absence. A Republican, Thomas was elected nearly two years ago.