Travelers on a plane about to take off in Glasgow, Scotland had a terrifying experience when they had to evacuate the aircraft because it filled with smoke.

The Jet2 aircraft was set to take off on Friday when the plane, heading for Alicante, Spain, started to fill with smoke. The pilot realized and made a sudden emergency stop before the plane took off. The 189 passengers on board the 737 were forced to evacuate and several were injured in the process.

"During the very early part of the take-off, smoke was seen in the aircraft and the cabin crew informed the captain and he stopped the take-off," Managing director of Jet2 Ian Doubtfire told The Herald.

The Daily Mail reports that at least 20 people were injured in the incident. Four people were hospitalized and 13 people were treated at the scene after the plane was evacuated. Some were injured while coming down emergency inflatable chutes.

Jean Walker, one of the passengers on board, told The Herald about her experience.

"It was terrifying. We were about to take off and the plane started shuddering and there were lights flashing and smoke and the crew started shouting 'Get out, get out'," Walker said.

"We were sitting at the wing and the girl opened the door and we went out on the wing, but there wasn't a chute there," she continued. "There were about eight or 10 of us on the wing and I was saying people couldn't come out because there was no chute. Two girls jumped off the wing on to the ground. They were OK.

"Other people got hurt coming down the chutes - they were inflated, but the hostesses were just shouting 'Jump, jump' and people were just banging into each other at the bottom, and about four people were taken to hospital," Walker added.

The incident caused other flights at Glasgow Airport to be suspended until 10a.m. after the incident. Six incoming flights were diverted to other UK airports  and five flights were cancelled. About 14 flights were delayed.

The airport has since reopened.

It is not clear what caused the plane to fill with smoke at this time.

Aviation writer Jim Ferguson discussed some of the possibilities with The Herald.

"Was there a little oil perhaps drifting around in the system somewhere that heated up and got into the air conditioning? It does happen. Obviously it shouldn't, but it does occasionally," Ferguson said.

"Oil is pretty sophisticated stuff in aeroplanes. I'm guessing it could even be hydraulic fluid or something," he continued. "But the fumes can be toxic, so you don't mess around."

Despite the reported injuries, no one was seriously injured.