Winnipeg police have issued a warning about what they’re calling a “bad batch” of illegal drugs.

At least five people have been sent to hospital, said police.

Witnesses said they saw eight officers struggle to restrain a man who had been running in and out of rush hour traffic at Salter Street and Selkirk Avenue on Thursday afternoon.

Sources told CTV News the man was exhibiting signs excited delirium, a condition brought on by a drug overdose that leads to bizarre behaviour, unexpected physical strength and paranoia.

The victim’s sister told CTV News the man suffers from schizophrenia but doesn’t take medication for it. She said, however, her brother is a known meth user. Thursday night, it’s believed he may have taken a bad batch of the drugs which caused his heart to stop for 10 minutes, causing brain damage.

Police issued a public advisory warning later that night about a bad batch of meth amphetamines, or its derivatives, being sold on the street.

“There were multiple instances of people either acting erratically or possibly having consumed some sort of illicit drug with similar symptoms,” said Const. Eric Hofley from Winnipeg police.

The Winnipeg Regional Health Authority said within a few hours, five people were treated in emergency rooms and were believed to be suffering from adverse reactions to the drugs.

“People can die from this. They do die from this,” said Dr. Alecs Chochinov from the WRHA.

“The nature of these substances is completely unpredictable and the reliability…completely unpredictable. It's never a good time to take street drugs,” he said.

Friday afternoon, CTV News is told an agitated man began taking off his clothes at a Notre Dame Avenue hotel and then got into a knife fight. Police are not saying if the incidents are linked to the bad batch, but officers are investigating that possibility.

One of the men was rushed to hospital in critical condition, while the other was taken in stable condition.

Police and health officials aren’t saying what’s in the drug that is making it so dangerous, but doctors do say there is no such thing as a good batch of meth since it’s an illegal drug, which means there’s no governing body to ensure what goes inside it won’t harm or even kill users.

Both medical and police officials say the only way to make sure you are safe is not to buy street drugs.

- with a report from Caroline Barghout