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A peaceful protest in Dallas over the recent videotaped shootings of black men by police turned violent Thursday night as an unknown number of people shot at officers, killing five and injuring seven, as well as two civilians.

Here is what we know about the officers that were killed in the line of duty:

DART Officer Brent Thompson, 43

Thompson was described as “courageous” and a newlywed, according to Dallas Area Rapid Transit police Chief James Spiller.

Officer Patrick Zamarripa of Fort Worth, 32

Zamarripa was a 2001 graduate of R.L. Paschal High School, where he played baseball. The 32-year old was born in Fort Worth and served three tours of duty in Iraq with the U.S. Navy.

Zamarripa was the father of two small children, one of whom is a student at Westcliff Elementary School. His widow, Kristy, is also a Paschal alum. He’s described as a kind, funny, loving, and heroic human being.

Officer Michael Krol, 40

Krol was from Redford Township, Michigan. His uncle, Jim Ehlke, said Krol had a passion for helping people — and that being an officer was his life dream.

Senior Cpl. Lorne Ahrens

Sources confirmed later Friday that the fourth Dallas police officer killed has been identified as Sr. Cpl. Lorne Ahren.

Michael Smith, 55

Officer Smith served as an Army Ranger and went on to attend the Lamar Institute of Technology. He leaves behind his wife of 17 years, and their two girls age 14 and 10.

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