Two officers discharged their weapons in the waiting room, killing a man just after 1:30 p.m. Wednesday. The province's Special Investigations Unit (SIU) is investigating the case.
Yvonne Morton was walking toward the hospital Wednesday afternoon when she heard someone scream.
"All I heard was gunshots, the chick's just like, 'Help, my boyfriend's shooting at me,' and she comes running out," said Morton. "I did see blood on her leg, though, and there was blood on the ground. I saw her collapse."
Another witness, Eric Brown, said, "I looked over and [saw] basically one of the security guards going inside, and then all of sudden came out real quick, and there was a lady in behind him with blood on her hands, screaming her boyfriend's shooting."
The woman Morton saw hasn't been identified, but police have confirmed that the shots she heard were fired by two Guelph police officers.
Guelph Police Const. Mike Gatto wasn't able to provide any further information about what sparked the shooting.
"I can't comment on any of the particulars of what led police to this location or why they were here or what led to the shooting or any of that kind of stuff, because it is an SIU investigation," he said.
In a release, the SIU said a man died in the ER after two police officer discharged their firearms, but the statement made no mention of a bloodied woman.
The hospital was locked down after the shooting, then reopened to the public later in the day.
As of Wednesday evening, the ER was still receiving patients, although some ambulances were being diverted to Cambridge and Kitchener.