Rescue crews recovered the bodies of two men killed when the trench they were digging suddenly caved in on Monday, police said.
Some time around noon, a large trench measuring nearly five metres deep, near Rossland and Westney roads collapsed, injuring two male workers and burying two others.
An Ornge air ambulance attended the scene and transported one person to hospital.
A second worker broke his ankle and was taken to a local hospital.
A large number of firefighters and heavy excavating equipment was brought to the scene, with crews slowly digging and reinforcing the edge of the trench through the night.
By about 2:30 a.m. Tuesday, Durham Regional Police said they found the bodies of the two missing workers.
They were carefully pulled out of the trench.
An Ontario Ministry of Labour investigation into what caused the collapse is ongoing.