A third worker, who was operating the loader, was airlifted out of the pit by helicopter but was not seriously hurt in the 10:45 a.m. accident, the Canadian Broadcasting Corp. reported police said.
One truck came to rest completely buried by gravel and the other was partially covered. Rescuers had not made contact with the two missing workers, the CBC said.
The quarry is near l'Epiphanie, Quebec.
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