Breaking News : First victim of the police shooting in Dallas

Snipers shot and killed at least five police officers on Thursday night during what had been a peaceful Black Lives Matter protest in downtown Dallas. Authorities said six other officers and one civilian were wounded in the “ambush-style” attack.

As some of the injured underwent surgery late Thursday and police continued to exchange gunfire with a fourth suspect, details of the victims remained scarce.

Four of the dead were Dallas police officers and the fifth victim was from the Dallas Area Rapid Transit force, according to police. Only the DART officer had been identified as of early Friday.

Brent Thompson, 43, joined the transit agency in 2009.

Department spokesman Morgan Lyons said Thompson was the first DART officer to be killed in the line of duty since the agency formed a police department in 1989.

“As you can imagine, our hearts are broken,” Lyons said in a statement. “This is something that touches every part of our organization. We have received countless expressions of support and sympathy from around the world through the evening. We are grateful for every message. Thank you.”

Thompson taught at Navarro College’s Police Academy in Texas in the early 2000s before working as an international police liaison officer for DynCorp International, a private military contractor, according to his LinkedIn profile. As part of that role, he mentored and trained police officers in Iraq and Afghanistan.