Const. Jennifer Sidhu said police were called to an address on Major Street, north of College Street, at 2:50 a.m., to report the robbery.
Three men surrounded the women and "grabbed their purses and took their personal property" before fleeing the scene, Sidhu said. One of the suspects appeared to be carrying a gun.
During the robbery, Sidhu said one woman was hit in the head with a rock, while another was dragged onto a lawn and "had her head hit on a bunch of rocks a number of times."
Both women were conscious and breathing after the robbery.
"It's a violent robbery in the middle of the night," said Sidhu, which is why police are urging anyone with information about the incident to contact them.
It is not immediately clear if the robbery is related to a knifepoint ATM robbery that occurred in the Kensington Avenue and St. Andrew Street area earlier this week.