​Dallas officer's heartbreaking last words before he left for work

Dallas will honor its fallen heroes at a vigil tonight at City Hall, where the victims' relatives will join their extended police family to mourn the lost officers.

The sniper shootings marked the nation's deadliest day for law enforcement since 9/11.

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A common theme emerging in the aftermath of the Dallas ambush, reports correspondent Omar Villafranca, is family, whether it's a wife or a daughter remembering a husband or father, or the police family rallying around its own.

Heidi and Mike Smith were living the American Dream. She's a teacher; he was a police officer.

On Thursday Heidi's worst nightmare came true.

"The hospital chaplain put his hand out to me. And I knew," she said.

Sgt. Mike Smith was dead. Before he went to work, without fail, Mike always said goodbye to his daughters Victoria and Caroline.

"I would always at least give him a hug before he left," Victoria said.

But on Thursday, something was different.

Caroline recalled, "He said to me, 'What if this is the last time you ever kiss me or hug me?'"

Villafranca asked, "Did he always say that?"

"No. It just felt different to me. I thought something bad was going to happen."

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Thirty-two-year-old Patrick Zamarripa; 48-year-old Lorne Ahrens; 40-year-old Michael Krol; and 43-year-old Brent Thompson were also killed in the attack.

Dallas Police Officer Jorge Barrientos saw three members of his unit shot down: "I had people very close to me, people in my unit, friends, brothers go down next to me, within feet of me."

The officers died doing what they had sworn to do: To protect and serve.

"They had no regard for their own life," said Shetamia Taylor, one of two civilians shot by the assassin during Thursday's protest. "They stayed there with us. They surrounded my son and I."

Nearby officers ignored the danger to rush to her aid. "I am so sorry that they lost their lives," Taylor said. "But I'm thankful. I am so thankful."

Late last night El Centro College confirmed two of its officers were injured in the deadly ambush.

Cpl. Bryan Shaw and Officer John Abbott both sustained injuries from the gunman. Shaw had bullet fragments lodged in his stomach, and Abbott was injured from flying glass.

Despite their injuries, both officers rushed back to the scene to help protect other officers and civilians.