Hundreds of people who watched the Parliament Hill light show and parked in the underground garage at the World Exchange Plaza got a nasty surprise when they returned to their vehicles on Wednesday night.

Only one exit from the garage was available due to construction, leaving drivers stuck in gridlock for more than an hour.

"Unfortunately we were stuck in the bowels of the World Exchange Plaza for over two hours, not moving an inch," said Scott May, who parked with his family to watch the light show.

Help! Stuck in world exchange plaza hell! Been an hour and not moving. Send food and water. Please. —@foodyscott

"They wouldn't open any emergency exits or open any way to expedite us out of the building ... Impark and Bentall really dropped the ball and had a very bad public relations mishap on their hands. They were not responsive and didn't really seem interested in expediting these people [out] at all."

'It wasn't safe'

Kim Vrieling, who went to the light show with a colleague's family and also parked underground, said they called Ottawa police for help.

"My co-worker and I ... we went upstairs into the facility ... to look for a security guard, and we actually ended up phoning the Ottawa police, just the dispatch line, to have them come and help because people were getting angry and there were lots of kids," she said by phone Wednesday night after getting home.

Stuck in the parking lot at World Exchange after light show. People haven't moved in an hour. <a href="https://twitter.com/hashtag/ottawa?src=hash">#ottawa</a> —@Kim_MusicFest

"They had locked the washrooms in the World Exchange Plaza so there were little children who had nowhere to go to the washroom and things like that. It was a big mess."

Aside from the discomfort, Vrieling said she and others also felt unsafe.

"You've got five levels of a parking garage and no one's moving? If something were to happen and the building had caught on fire, how would those people have gotten out?" she asked.

"You have to look at it from a security standpoint, and it wasn't safe to have all those people sitting there idling in their cars for that long."

Here's what some other people Tweeted from the garage.

Avoid parking @ World Exchange Plaza. Couldn't get to car, then it took almost 2 hours to exit while my wife & kids froze, locked outside. —@Matthew_Davidge

<a href="https://twitter.com/Impark">@impark</a> Ottawa World Exchange...<a href="https://twitter.com/hashtag/notimpressed?src=hash">#notimpressed</a> with your service tonight! Had to pay 2 times! Waited over 1hr to get out! —@alobe

<a href="https://twitter.com/onthebeat1">@onthebeat1</a> it has been 45 minutes since I last tweeted. We haven't moved the speedometer yet. <a href="https://t.co/NvOhFUttT5">pic.twitter.com/NvOhFUttT5</a> —@Kim_MusicFest

<a href="https://twitter.com/Ottawa_Traffic">@Ottawa_Traffic</a> people stuck in world exchange plaza underground parking lot for over an hour <a href="https://t.co/ZNMH3axHPL">pic.twitter.com/ZNMH3axHPL</a> —@JerGirouard

Some drivers couldn't get in, either.