Jacob Adams was taking a nap at the gate of his departing flight from Brussels' Zaventem airport on Tuesday when he was startled awake by the sound of an explosion.

"I wasn't exactly sure what it was, then I heard the screaming and yelling, and I was trying to figure out what was going down," Adams, a student from Kamloops, B.C., told CTV News Channel.

"Then people were saying, 'Get down, get down.'"

Adams then hid underneath a chair until a stewardess told him that they had to get out of the airport. He followed her out on to the tarmac and eventually took a shuttle to the relative safety of an evacuation zone at the side of the airport.

Adams estimated he was within 85 metres of one of the two explosions that wracked one of Belgium's airports at 8 a.m. local time on Tuesday. He said he could see the smoke billowing from the floor below him, but couldn't see any of the victims or bombers.

"I thought maybe there's a fire or electrical shortage, or something like that,” he said. “I really had no idea."

Islamic extremists have taken responsibility for the attack on the airport, as well as another in the subway, which killed at least 34 people and wounded scores of others.

The Kamloops native said his "real fear" kicked in when he was in the evacuation area with hundreds of other people.

"I thought maybe the plan was to get everyone evacuated to an area and then maybe bomb that area, and that’s when I really was my most scared," said Adams.

Adams proceeded to call his parents back in B.C., where it was 1 a.m., to tell them he was "safe" but "really scared."

"Both of them were definitely freaking out," he said. "My dad took the (phone) and he was like, 'Are you safe? Are you alright?'"

And I was like, 'Yeah, I'm pretty scared,' and they just told me to ‘stay on the line … it is going to be alright, just stay strong, listen to the people and follow the directions.'"

Adams said he stayed on the phone with his parents for another 20 to 30 minutes, and it was two hours before he felt safe again.

"Until I left the airport and got to an airport hotel with some other people, that was the first time I actually felt like I didn't fear for my life," he said.

Global Affairs Canada says Canadians in Belgium should "exercise a high degree of caution due to the current elevated threat of terrorism.

Canadians who require consular assistance in Brussels can also call the embassy at 32 (2) 741-0611, or contact the Emergency Watch and Response Centre in Ottawa by collect call at +1 613 996 8885 or by email at sos@international.gc.ca.