A Sheridan Mall security guard is recovering in hospital after she suffered stab wounds during a scuffle with a shoplifter.

Police say they are still on the hunt for a suspect who was allegedly trying to steal baby formula from the Zellers store at the North York shopping centre.

The plain clothes security guard approached the suspect and they got into a physical altercation, a witness told CTV Toronto.

"I noticed a girl with blood running all down the back of her," said Mona Sugden, who witnessed the incident at the mall early Tuesday evening. "I asked her if she had been shot and she said: 'No. I've been stabbed.'"

Retailers say they've seen a surge in baby formula thefts, which has led to it being kept behind the cash registers in some stores.

Diana Graham complained that good baby formula is expensive which is why it's sold for less on the black market.

"That's why people in need go to the food bank and they only give enough formula to last the baby three days and that's not going to get them past the week," she said.

Police say they have a good description of the stabbing suspect and are looking at footage from a surveillance camera for evidence.

Witnesses say they have seen the suspect around the area before.

The plain clothes security guard remains in danger of losing a kidney as a result of being stabbed.

With a report from CTV Toronto's Austin Delaney