DALLAS — As the gunfight raged at the back door of the Earle Cabell Federal Building Monday morning, Tom Fox is the man you can see in cellphone video hiding in a corner. Bullets fly past him in both directions, and he is armed only with a camera.

"I just crouched in the corner and tried to make myself as small as possible and just prayed, just prayed, that he didn't walk past me.

"If he saw me sitting there with a camera I have no doubt he would have shot me."

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Moments earlier, the Dallas Morning News photographer — who was at the federal building on a completely unrelated assignment — had taken the photo you see behind him in his television interview. Fox says he heard what he first thought was a car backfire. But he pointed his camera down the block when he saw something that looked suspicious.

"I didn't know what it was, so I just pulled up a long lens and looked through the viewfinder and saw the muzzle of a gun and the mask on."

The gunman, later identified as Brian Isaack Clyde, seemed to be staring right at him.

"So I was running down the sidewalk thinking I gotta get out of harm's way, he's coming this way. I didn't want to be shot in the back. And so I ducked into the first alcove which happened to be the first one by the glass door at the back of the building."

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And that's where he stayed until the final gunfight. The gunman fired into the south entrance of the federal building, just feet away from where Fox was hiding. But when officers returned fire, the gunman stumbled into a parking lot, where he collapsed. The gunfire lasted less than a minute.

"But when you're sitting there and you're just praying that he's not going to shoot you, it just lasts forever."

Next, Fox was shooting video. Posted on YouTube by the Dallas Morning News, it's obvious he doesn't yet know where the gunman is and doesn't know he's dead or dying in the parking lot and that the threat is over.

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But moments later, in additional cellphone video captured from the vantage point of an apartment building next door, there Fox is again, back at work capturing the gunman's final moments.

"When they had ripped his mask off, and I saw his face and this young man, I couldn't believe it. I was like, 'Why? What is your anger? Your life is not worth this.'"

As for his own life, Fox thanks the officers who neutralized the threat. Tonight, he can be home with his own family.

"I'm just thankful they were there and thankful the gunman didn't come any further than he did.

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"In this news business, you see a lot of things you really don't want to see or have to witness. And you kind of like, put it aside on a shelf somewhere and deal with it at an appropriate time, and I think that's what I'll do."

His Father's Day celebrations were cut short on Sunday by more bad news: another night of violent North Texas weather. His plan Monday is to go home and hug his family and make sure the family celebration has the happy ending it deserves.

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"So hopefully I can go home tonight with my family and throw those steaks on the grill and spend it with them, and be grateful tonight."