MONTREAL -- Montrealers were startled awake around 3 a.m. Thursday thinking the ground might be shaking, but it turns out it was the heavens jolting them out of their slumber.

"We, too, received about 30 reports of something strongly felt in and around the west end of Montreal Island, between 3:20 and 3:30 a.m.," said seismic analyst Nick Ackerley of the Canadian Hazard Information Service.

Both the Earthquake Track and Earthquakes Canada websites reported no earthquakes in the region, which Ackerley confirmed by checking seismographs in the region.

"Clearly a lot of people felt something frightening, but it was likely related in some way to the fierce thunderstorm that rolled through around that time," he said.  

A low pressure system hit the region overnight which brought rumbles of thunder with it.