A new twist on credit card phishing scams has emerged in Canada that targets people early in the morning when they are sleepy and potentially vulnerable, according to the federal government's Canadian Anti-Fraud Centre.

Daniel Williams, a senior call-taker from the anti-fraud centre, says the scam begins with a phone call between 5 a.m. and 7:30 a.m.

The caller claims to be from the victims' bank and says a credit card was used without authorization the previous evening.

Williams says because of the early hour, the victim will often volunteer information.

"The consumer lets them know who they bank with, then the suspects will read out the first few digits of the credit card which is standard for that bank, that credit card," he said.

Williams says the scammers then ask the victim for the next eight digits to confirm their identity.

Once the scammers have the complete card number, they immediately use the information to make purchases on the account.

Williams says the phishing scam is quite successful, and that anyone who has been victimized should contact the police.