An Edmonton family is accusing nurses of assaulting a mentally-ill woman so severely that she had to be sent to the emergency room.

"Like, her lips were sliced right open. Stitches, blood everywhere. The goose egg on her head," Michelle Goltman told CBC News.

Goltman says her sister, Lisa, was rushed to the emergency room Monday night after she was found injured.

She says staff called the family and said that the 22-year-old, who suffers from schizophrenia and is bipolar, was found lying in a pool of blood.

They said she had been in her room when she slipped on her own urine and was unresponsive.

Goltman says the family spent hours at the University of Alberta hospital, waiting for news on Lisa’s condition.  When they saw the extent of Lisa’s injuries, they became suspicious. She had multiple injuries to her head and two black eyes, which didn’t seem consistent with a fall.

"She was a mess. She was in so much pain, she didn’t even know she was in pain," Goltman said.

"She came in on a stretcher, covered in blood."

When she was able to speak, Lisa told the family that she was beaten by a man.

Goltman says a doctor at the University of Alberta hospital told her the injuries did match the story.

"He said ‘there's no way, no way this could be a fall.’"

Goltman’s family then contacted police. That’s when they were called by a hospital official, telling a different story of what happened.

"She said that she got the wrong information from her staff.  That it happened in the common area, not in her room... well, they're hiding something," Goltman said.

Goltman says they were told that two nurses were involved in the incident -- one male and one female.

Police, AHS investigating

Edmonton police wouldn’t comment on the case, but did say that they have opened a preliminary investigation.

Alberta Health Services tells CBC News the family’s claims are "being investigated and reviewed internally."

"We have been discussing, and will continue to discuss, this matter directly with the patient’s family," spokesman Kerry Williamson wrote in an email.

He said the department would not comment on specifics of the case, citing patient confidentiality.

Goltman says the family has had concerns about Lisa’s stay in the hospital in the past, and that they have spotted bruises and marks on other occasions. But Lisa was never able to say what caused them.

"She won’t confess it to us, because she’s terrified. And now we know why she’s terrified, because of what they’re doing to her," she said.

"They should be charged with what they’ve done."

The family is meeting with police tonight with the hope of learning more about what happened.