McGill University has ordered an investigation into some debit and Interac machines on campus after several students reported card fraud known as "skimming."

CBC has learned that at least five McGill students were recent victims of card fraud and lost between $300 and $700 since the start of the year.

The school administration is not commenting publicly but confirmed it is investigating alleged debit card cloning and fraud at the McGill University bookstore — although the university said it does not yet know what is at the root of the problem.

Sophomore student Alex Brown said she found out she'd been robbed last month after receiving a call from the Royal Bank. "They were like, 'We were curious.… Did you take out $300 this afternoon from your account?'

"And I was like 'no' because my bank monitors my regular [transactions] and I don't usually take out $300 at a time from like a coffee shop," Brown said in an interview with CBC News.

In all, she had $700 stolen from her account, and claims she had many friends who also received similar calls from their banks.

She was eventually reimbursed.

Card-skimming involves copying electronic data from a customer's debit-card and personal access codes, usually using equipment such as card-reading devices and hidden cameras.

The stolen data are encoded on counterfeit cards, used to withdraw funds from victim's bank accounts.

Canada's Interac Association said skimming is a growing problem across the country but there are ways to protect your accounts.

"Cardholders should always protect their PIN using their hand or body: That's one of the key tips," said association spokeswoman Tina Romano.

People can also protect their bank accounts by allowing their debit cards to be swiped just once during transactions.

The association also recommends bank account holders check their financial statements regularly. 

The bookstore won't comment on the investigation.