A staff member answered the phone just after 1:30 p.m. and heard a male voice say: "The building is going to blow up in five minutes."
Staff called the RCMP, pulled the fire alarm and evacuated the building. "We have to be safe," said Community Ministries coordinator, Patricia Gervais.
She said RCMP and the fire department arrived quickly and searched the building, but detected nothing suspicious.
Staff and residents were allowed back into the building after 45 minutes.
Gervais said they didn't reveal the reason for the evacuation to all staff and residents until after police arrived.
"Some of them laughed, figuring it was a joke," said Gervais.
Neither the Salvation Army or the RCMP know who made the threat.