As Houston Police Chief Art Acevedo was giving news of Sgt. Harold Preston's death during a press conference Tuesday, he also told the story of a witness who risked his own life twice to make sure another officer -- Officer Courtney Waller --  was moved out of harm’s way.

Acevedo didn’t give that man's name at the news conference, KHOU reports.

According to Acevedo, the man – who he described as African-American, shirtless and covered in tattoos – was at the front of the complex washing his car. Acevedo said the man noticed the police activity and began recording on his phone.

“But when the shooting rang out, he didn’t just continue to film, like so many people are doing in this upside-down world. This young African-American male, who told me he was a gang member, that his life was way out there, but he’s found God and has turned his life around. He went and helped Officer Waller.”

Acevedo said the man helped Officer Waller -- who had been shot in the arm -- put his tourniquet on. He then helped the wounded officer to safety.