TORONTO -- Residents who were evacuated from their North York Homes following a gas leak are being allowed to return home, Toronto police say.

Emergency crews were called to the area of Jim Baird Mews and Judy Sgro Avenue, south of Sheppard Avenue West, sometime before 10 a.m. after receiving a report of a gas leak underground.

Toronto Fire Services said there were "explosive levels of gas" in the storm sewer system.

No injuries were reported, but 20 townhomes within a four block radius of the leak were evacuated.

TTC buses were brought in to shelter residents.

At the height of the incident, Toronto Fire had five trucks attending the scene.