It didn't take long for him to realize it was the real deal. One look at the faces of the shoppers running for the exits told him all he needed to know.
"It was instant panic," Lawrie said Sunday morning. "It was almost like as if you stepped on an anthill and then everyone just flooded right out of the whole place. It was one of those things that you almost think, 'was it real or was it not?'
"You've just got to get out of there. You can't sit and wait around. So I just got out of there as fast as possible."
Police investigators were hunting for the shooter Sunday and reviewing security video. The shooting left one person dead and injured several others.
Lawrie said he was in the area of the shooting — a busy food court — just 10 seconds earlier. He and a friend were walking up from the mall's lower level when they heard the gunshots.
"As soon as we were going up the first flight of stairs we heard just like, bang bang bang bang bang, as fast as you could pull the trigger," Lawrie said. "We were kind of skeptical on what we heard. Sure enough we turn around and there's a bunch of people running up the stairs. Usually these people wouldn't be running out of a public place like they were.
"So that was a trigger to myself and to my buddy to get out of there as fast as possible."
Lawrie took to Twitter shortly after leaving the mall. He was one of the first people to provide a first-hand account of what was happening.
"Pretty sure someone just let off a round bullets in eaton center mall .. Wow just sprinted out of the mall ... Through traffic ...," Lawrie tweeted.
He then described a chaotic scene in his next tweet.
"People sprinting up the stairs right from where we just were ... Wow wow wow."
Lawrie, who has over 125,000 followers on Twitter, also tweeted a picture of the scene outside the mall that was featured prominently on news websites.
"I just thought I'd give it out there to anybody that could have been in the mall or anybody that needed to get there asap, that I thought I could give them a good piece of information," he said of his tweets.
The Langley, B.C., native was one of the first people to reach the exits.
"It was get out of there as fast as possible," he said. "Get safe, get to a place where you know you're going to be all right and then just analyze what was going on."
Earlier that afternoon, Lawrie and the Blue Jays dropped a 7-4 decision to the Boston Red Sox at the nearby Rogers Centre.
Lawrie and his friend weren't shopping for anything specific at the mall. They were on their way to an electronics store across the road when the shooting occurred.
"It's crazy. It's one of those things that you think would just never happen," Lawrie said. "I just found myself in a weird place at the wrong time. I'm thankful that I'm OK and hopefully everyone else is going to be OK that was inside. One person dead, so it was just one of those things where you've got to realize where you're at in your life. I'm happy that I'm OK."
After the shooting, Lawrie tweeted that he was "Rattled right now."
"The more I thought about it, I was just glad that I was with my buddy because we talked about it a little bit," Lawrie said. "But the more that I thought about it, it was just like that I did get lucky because we were right down there 10 seconds before so you don't know what could have happened."
Blue Jays manager John Farrell was also asked about it before the game.
"It's an unfortunate situation and certainly all of our thoughts go out to those who are affected by it," Farrell said. "But thankfully as it relates to us, the fact he was there, he did what he felt was right and tried to make other people aware of the situation. I think he did the right thing by evacuating."
A moment of silence for the victims of the shooting was observed before the series finale against the Red Sox.
Lawrie, 22, is in his first full season with the Blue Jays. He entered play Sunday with four home runs, 21 RBIs and a .276 batting average.
Also on HuffPost