Fire crews and members of the CPS Arson Unit are investigating after a fire at a southeast apartment building overnight.

The fire department was called to a four-storey apartment building in the 2600 block of 16 Avenue S.E. and when they arrived, they found a small fire inside one of the units.

Residents in both of the neighbouring suites were told to leave while crews quickly knocked down the fire.

No one was injured as a result of the incident and the displaced residents were allowed to return home afterwards.

Police have confirmed that a person was arrested at the scene in connection with the fire, but provided no other details.

Fire investigators and the Arson Unit are working to determine the cause of the fire.