A DART (Dallas Area Rapid Transit) police officer receives comfort at Baylor University Hospital emergency room entrance on July 7 in Dallas. (Ting Shen/The Dallas Morning News)

A Dallas police officer crumbled to his knees near a cop car. Gun dangling from hip, he hid his face in his hands.

Another wept as he was comforted at a Baylor University Hospital emergency room Thursday night.

After a shooting in the Texas city that left five officers dead, glimpses of raw emotion from police were shared across the Internet.

Tom Berry, founder and director of law enforcement charity Blue Alert Foundation, said he noticed that support for police had burgeoned since the shootings Thursday evening. He said he woke up to hundreds of thousands of notifications and positive messages on social media for Blue Alert, which aims to support the families of officers killed on duty.

It was the deadliest day for law enforcement since 9/11. “These are merely guys walking down the street doing their job during a protest, a peaceful protest,” Berry said. “Police were happy with what was going on until a couple people on elevated buildings decided it was open season on anyone wearing a badge.”

Names of the slain officers from Thursday’s shooting spree were released Friday. The family of 32-year-old Patrick Zamarripa, who had served three tours in Iraq, said he just liked to help people.

“He comes to the United States to protect people here,” his dad told The Post’s John Woodrow Cox. “And they take his life.”

Brent Thompson, 43, recently married. Dallas Area Rapid Transit Police Chief James Spiller said Thompson was “in great spirits from his recent marriage.”

“This is very heartbreaking for us,” Spiller said.

“We don’t even know if he had a honeymoon or not,” Blue Alert Foundation’s Berry noted. “What do you tell a wife who already had it in the back of her mind that her husband could lose his life while at work, when two weeks later it becomes a reality?”

There are about 3,400 officers in the Dallas Police Department. Even with a force that size, “it becomes a brotherhood with law enforcement,” Berry said. “They both have to have each other’s back when they’re out on the streets. It’s not just that you’re watching for yourself. You have to have absolute, 100 percent trust in them to watch your back as they watch their back. That’s just the way it is in any law enforcement agency.”

So, when an officer is slain, that grief is much greater than simply a co-worker dying. “It’s a family,” Berry said.

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