Arson detectives are now helping in the investigation to find the cause of the fire at a seniors complex on the city's south side.

The early morning fire on Sunday has resulted in $15 million in damages. Fire investigators said the damage includes $10 million to the building and $5 million to contents.

Fire crews arrived at the 4-storey complex just after 3:30 a.m. in the area of 106 Street and 40th Avenue.

About 160 seniors are now homeless after the blaze. Many were able to return to the building Monday to try to find some of their necessary items like medications and important documents after firefighters allowed them the access.

87-year-old Marian Gauld said a bathrobe is all she has for now.

"This (bathrobe) is all I have and I can't get any clothes out, they say I can get my purse and medications," she said.

Public information officer with the Edmonton Fire Department, Melanie Mochoruk, confirmed 16 units were affected by the blaze, and said 18 units responded to the incident, which is classified as a three-alarm fire.