Fredericton father and son describe being trapped in their apartment as shooting unfolded

When Brett Gibbons was awoken by the sound of gunfire Friday morning, he said it was "like a hammer" right next to his ear.

"The loudest sound I ever heard," the Fredericton man told As It Happens guest host Matt Galloway​. 

Still, Gibbons said he couldn't fathom the possibility of a shooting in the quiet neighbourhood he grew up in. So when he didn't hear any sirens, he decided it must have been someone using a nail gun, and closed his eyes to go back to sleep.

"And then boom boom boom — it goes off again," he said. 

That's when his dad came into the room and said: "There's something going on here."

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• TIMELINE: How the Fredericton deadly shooting unfolded

Among the four people confirmed dead in the early-morning shooting are Fredericton police officers, Lawrence Robert Costello, 45, and Sara Mae Helen Burns, 43.

The names of the two civilians killed have not been released.

The suspect is in custody and being treated for serious injuries. The neighbourhood was locked down and people were told to stay inside their homes.

Gibbons' father John said he immediately recognized the sound of gunshots Friday morning  — but he didn't fully grasp the scope of the situation that was unfolding.

"​I thought maybe someone was just firing off or whatever," John Gibbons told Galloway, "but then I looked out and we were basically swarmed by police."

Trapped for hours

The father and son duo have since been moved to an arena with other evacuees as the investigation continues.

But for two hours on Friday morning, they were trapped in their apartment complex as a tense standoff unfolded at a neighbour's apartment some 15 metres away.

"Honestly, I didn't believe it at first because it just happened so fast," Brett Gibbons said. "Like, there was just police everywhere. Didn't know what was going on, and then it progressively just got crazier."

Meanwhile, his friends were texting him conflicting information about what was happening and it became difficult to separate fact from rumour.

Worst-case scenarios flashed through his mind, he said.

"I was just thinking, what are we going to do next? How are we going to get out?" he said. "If [the shooter] comes into our place, we'll have to leave, we'll have to run — do anything we can."

'I felt like I got shot'

Eventually, more police showed up on the scene — with armoured vehicles that started firing tear gas into a window where the shooter was believed to be. 

"The weirdest feeling I ever felt in my life was once the police shot into the window, I felt like I got shot," Brett Gibbons said.

"Instantly my whole body went into shock and I was so afraid that I was shot and felt like I had to search my body."

The pair are now safe and sound, but Brett Gibbons is still shaken.

"I literally grew up in the area — my childhood neighborhood that now I forever have a scar on," he said. 

"It alway seems to be somewhere else. It's always far away. It's always in a different city. But then when it's finally at your front door ... that really kind of made me realize how scary it was and how real it was."

Written by Sheena Goodyear with files from CBC News. Produced by Jeanne Armstrong.