Austin police have arrested and charged a man they say is responsible for the death of an Austin-based architect earlier this month.

On Thursday, police charged 22-year-old Preston Joe Sharpnack with manslaughter, a second degree felony, in the death of 35-year-old Matt Casey.

Casey was pronounced dead on Sept. 10, about one week after he was assaulted on East Sixth Street. Officers say Casey engaged in a “verbal altercation” with a male and a female, both in their mid 20s, during the early morning hours of Sept. 3. Shortly before 1 a.m., officers found Casey collapsed to the ground on the corner of Sixth and Neches.

According to an arrest affidavit, witnesses told police that Casey was punched a single time by the male suspect.

Review of surveillance video from the area provided officers with a description of the male suspect, including prominent tattoos, which led to an anonymous tip suggesting the suspect was Sharpnack.

When approached by police, Sharpnack voluntarily agreed to be interviewed and said, “That’s crazy. I only hit the guy one time.”

The affidavit says Sharpnack told police that he and his female friend, who he identifies as “Renee,” had asked Casey and his friends for spare change. The two groups began cursing at each other and, according to Sharpnack, both groups exchanged swings, but Sharpnack hit Casey just one time.

According to the affidavit, Sharpnack identified “Renee” as a homeless Hispanic female who lives in South Austin.

Shaprnack said that he only discovered that Casey had died a day before he was approached by police and told them he never intended to kill anyone.

“I do have remorse,” Sharpnack told the police. “That’s not how that thing was supposed to be. It was supposed to be a defense.”

Police spoke to another witness who said the punch against Casey came “out of nowhere.” No one in Casey’s group of friends knew why the pair was confronting them.

Sharpnack was booked into Travis County Jail and is being held on $150,000 bond.