Dozens of people were evacuated from a Flemingdon Park seniors’ residence early Wednesday morning after high levels of carbon monoxide were detected in the building.

Toronto Fire crews were called to a building on Deauville Lane, near Don Mills Road and Eglinton Avenue, after carbon monoxide detectors went off on the 4th, 5th, and 6th floors.

The superintendent told Toronto Fire Services that the air conditioning unit had recently been repaired and the unit was turned off after a “burning smell” was reported in the building.

The entire building was evacuated and about 85 to 100 people, including several people in wheelchairs, required shelter. Two TTC buses were brought to shelter people from the cold.

Enbridge was called to the scene and inspected the air conditioning unit while firefighters ventilated the building.

Carbon monoxide readings eventually returned to normal and residents were allowed to return to their units shortly after 4 a.m.

The cause of the high readings is still under investigation.