A rescue operation is underway following an apparent landslide at a quarry, with two workers missing near L'Epiphanie, Que.
They are trapped under the earth at a gravel quarry just east of Montreal.
A third worker managed to escape.
The torrent of earth swept along two trucks and one excavation vehicle, which collapsed into the quarry Tuesday morning. The excavator had been used to fill the trucks with gravel at the site, which is operated by Maskimo Construction Inc.
"For reasons we can't explain there was a landslide," said provincial police spokesman Benoit Richard.
"The two trucks, and the excavator, completely fell, or descended, into the hole."
Provincial police are leading the rescue effort.
Authorities are having trouble accessing the area and have had to call in a helicopter.
The helicopter has arrived at the site to whisk away the worker who escaped.
Richard explained why it was difficult to get to the site.
"The terrain was completely broken, the road too," he said.
"So we have no means of getting into the hole to help those people."