A former security guard at St. Michael's Hospital in downtown Toronto says assaults by some guards on homeless and intoxicated people have been a problem for years.

Last week, the hospital fired two security guards after surveillance video showed them beating up an aboriginal couple. The guards are also alleged to have shouted racial slurs during the attack.

The man, Cliff Hussin, suffered broken ribs and was treated for a punctured lung.

Hussin, 36, has admitted to the media that he and his wife Donna Oakes were loud and drunk when they visited his cousin at the hospital on Feb. 4. They said the trouble started after they were told to leave.

"They [security guards] started getting a little abusive to, like, Donna. They were grabbing her and telling her — telling us — 'You natives are nothing but trouble' and that we were drunks and will never amount to anything. It was horrible," said Hussin.

Oakes said her husband was kicked unconscious by security guards and then dragged outside by his hair.

Hospital officials said they are surprised to hear of more cases of abuse.

But the guard, who asked to remain anonymous, said attacks by some security staff on homeless people aren't unusual, especially when they challenge their authority or harass other hospital personnel.

"If you are a drunk or a drug user they would kick you. They would kick you when you were on the ground or standing and they would stomp on you, and they wear steel-toed boots," he told CBC News.

The guard said he knew of beatings as far back as the SARS crisis in 2003 when a guard was suspended for using excessive force on a patient who pushed him.

"She pushed or touched his shoulder and he punched her in the face — hit her hard enough that she stumbled backwards," he said.

He also described an assault by another guard that led to criminal charges

"From my understanding he's been suspended for sexual assault on a psychiatric patient that was registered at the hospital," the guard said.

Police confirmed the attack took place last July, and that the case is expected to go to trial in August.

Hospital president Jeff Lozon said the hospital has acted when security guards have behaved inappropriately, including the dismissal of two guards last week who were caught on camera beating up Hussin and Oakes.

"It's not been a great situation for us but we have dealt with it effectively and appropriately; we have zero tolerance on this issue," he said.

The hospital, which is investigating the incident, is expected to apologize to Hussin and Oakes this week.