Pictured: Newlywed Transit Officer and Married Iraq Veteran Among 5 Dallas Sniper Victims

Officer Brent Thompson and Patrick Zamarripa were among the 5 killed officers.

The five officers shot dead in downtown Dallas Thursday night have been identified.

Brent Thompson, Patrick Zamarripa, Michael Krol, Michael Smith and Lorne Ahrens were killed and seven other officers were injured when shots began at 8.45 p.m. local time Thursday, according to the mayor’s office. Two civilians were also wounded.

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Thompson, 43, was the first Dallas Area Rapid Transit officer to be killed in the line of duty since the department was established in 1989.

DART Chief James Spiller told the Today show Friday that the officer, who joined the agency in 2009, had married another DART officer just last month.

"Our hearts are broken," DART said in a statement. 

Before joining DART, Thompson worked with U.S. police officers in Iraq and Afghanistan for the military contractor Dyncorp, according to his LinkedIn page.

Another slain officer, Patrick Zamarripa, was identified by his family on Twitter. His stepbrother, Dylan Martinez, shared a photo of Patrick with his father.

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"No father should have to bury his son. You are a hero, Patrick. Love you man," he wrote. Zamarripa was a family man and a military veteran, he said.

Zamarripa, 32, joined the Navy in 2001 and served in Virginia, Florida and Bahrain before transferring to the Navy Reserve in 2009.

Zamarripa's father told The Washington Post his son had completed three tours in Iraq.

"He comes to the United States to protect people here," his father said. "And they take his life."

On Zamarripa's Twitter page, he had written: "Addicted to the thrill of this job. I own the night. I love my Country, Texas, Family, God, Friends, and Sports! Don't Tread on Me! 'Merica."

Photos on social media show him with his young daughter. He also leaves behind a wife.

Photos show Patrick Zamarripa, one of the officers shot dead in Dallas Thursday. (Twitter)

Michael Krol was also among the deceased, according to Benny Napoleon, the sheriff of Wayne County, Michigan. Krol, 40, worked for his department's jails between 2003 and 2007 before moving to Dallas, he said. 

"We are saddened by the loss of the dedicated officers in Dallas — one of whom was a former member of this agency — and also the wounding of the other officers," Napoleon said in a statement Friday. "Those officers made the ultimate sacrifice and died honoring their oaths to protect and serve. Our thoughts and prayers go out to their families and also the Dallas Police Department."

Michael Krol was also among the victims.

Dad of two Michael Smith, 55, who had served as an Army Ranger, and Senior Corporal Lorne Ahrens, who had been with the department for 14 years, were also among the killed officers, WFAA reported Friday.

Family told NBC5 that Shetamia Taylor, 37, was among the civilians injured in the gunfire. She was shielding her children from the bullets, her sister told the channel.

The shooting unfolded when anti-police brutality marches were underway following the deaths of Alton Sterling in Louisiana and Philando Castile in Minnesota. Both men were shot by police officers in incidents that are now under investigation.

A suspect was killed in an explosion detonated by police following a standoff Thursday night, Police Chief David Brown said Friday, denying reports that the gunman had killed himself. Before his death, the suspect said he wanted to kill white people, especially white officers, Brown said.

The suspect told police that he had acted alone.

Brown shared his heartbreak in the wake of the violence. 

"We're hurting," he said. "Our profession is hurting... We are heartbroken. There are no words to describe the atrocity that occured to our city. All I know is that this must stop, this divisiveness, between our police and our citizens...

"Please pray for our strength during this trying time."

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