SIOUX FALLS, S.D. — A South Dakota man pleaded guilty Friday to cutting off the nipples of his ex-girlfriend during an assault in 2016. 

Tony Deval Ledbetter, 45, of Sioux Falls was arrested in October on a charge of domestic aggravated assault. He originally pleaded not guilty to the charges.

During a change of plea hearing Friday, Ledbetter pleaded guilty to all three counts of aggravated assault. Each count carries a maximum penalty of 15 years. As part of a plea deal, the state agreed to ask for no more than 30 years.

Ledbetter sat quietly throughout the hearing, apart from an occasional "Yes, sir" or "No, sir" in response to questions.

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Police said Ledbetter and his ex-girlfriend were arguing about their relationship on Oct. 11 when Ledbetter punched her, slammed her head on the ground and tried to get her to stop screaming by putting pressure on her throat with his forearm.

The man also tried to stuff a blanket in her mouth, police spokesman Sam Clemens said after the incident. 

At that point, Ledbetter went into the house and grabbed a pair of scissors. He then sat on her and cut off her nipples, Clemens said.

The woman was able to break free from him and ran outside to get help, Clemens said. Ledbetter ended up calling 911.

Two of the counts Ledbetter pleaded guilty to regarded the scissor attack, while the third stemmed from Ledbetter choking the victim.

Ledbetter's sentencing will take place on Nov. 28.