Fire crews had to evacuate a number of residents from a seniors centre in northeast Calgary after a large amount of smoke was spotted inside the building.

They were called to the building at around 4 p.m. on Thursday afternoon and were advised that smoke was seen on the second floor of the facility on Country Village Cove N.E.

People in the affected area were immediately evacuated out of the centre, including people who are completely immobile and needed to be moved in beds.

Investigators soon found that the smoke was coming from a rooftop heating unit.

Crews ventilated the building and all of the units, except for those on the upper floor closest to the heating unit, were found to be safe.

The cause of the fire is still under investigation.

No one was hurt in the fire.