Vancouver police say the attack happened at around 5:30 a.m. in the convenience store located on Denman Street, at Comox Street. The woman was stabbed multiple times, and rushed to hospital with serious injuries.
The suspect, a 39-year-old Vancouver man was wrestled to the ground by witnesses and held until police arrived.
Police say the man is known to them, but the motive for the attack is unclear.
Police said the attack "appears to be random."
Late Sunday morning, police reported that the victim was in stable condition in hospital.