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IRVING (CBS 11 NEWS) – Phillip Roberts says he’s sorry. The 33-year-old suspect is charged with stabbing Catherine Beyene with a screwdriver while she was working out on a treadmill early Tuesday morning, at a fitness center at State Highway 183 and Story Road.

READ: Good Samaritan Saves Woman From Gym Screwdriver Stabbing

Roberts says he’s still trying to figure out what he did. “I’m sitting in jail, all these things have hit me at one time, and I’m saying to myself, ‘what have I done?'”

The 911 calls make clear what happened inside the gym. One caller told a dispatcher, “I work at the 24 Hour Fitness on 183 and Story and there was just a man who assaulted a woman. We have a few men who are holding him down. He just jumped on her and started attacking her.”

Beyene’s husband says his wife has a punctured lung and stab wounds in her back. In a brief phone interview with CBS 11 News Tuesday night, he said his wife thought she was having a nightmare.

A spokesman at Parkland Hospital says it has no additional information about Beyene’s treatment.

Her husband didn’t return our calls Wednesday.

Roberts says, “It’s obvious that she didn’t deserve it.”

We checked Roberts’ mental health status. Officials with Dallas County would only tell us he’s being housed in the jail’s medical facility. Irving police say they have nothing official indicating any mental health issues. We found no criminal background in Texas and Tennessee, where Roberts says he’s from.

Roberts did confirm he has a membership to the 24 Hour Fitness and that he’s been homeless for six months. In fact, he told me he had the screwdriver in his pocket, in the first place, for protection.

To his victim Roberts said, “I want to tell her that I apologize, but I don’t think that’s actually enough to pay for what she had to suffer.”

Roberts is being held on $200,000 bond.

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