Tap-and-go credit cards are convenient for consumers, but Victorian police say they are also convenient for thieves.

Victorian Police Chief Ken Lay says tap-and-go credit cards have been a key factor in a 5 per increase in crime across the state.

But big banks and MasterCard have disputed the claims, though Mr Lay remains adamant that the number of “deceptions” had increased by 11,600 and impacted overall crime rates.

“Deceptions” describe when thieves fraudulently used other people’s credit cards.

“We’re seeing many, many theft of motor cars, handbags and burglaries where people are looking for these cards, are getting hold of them and within hours of getting them, they’re going into stores and using them,” he told the ABC.

“So you’re getting this flow-on effect … mainly because of these types of offences.”

News outlets have reportedly received a statement from MasterCard, which said that it has discussed the issue a number of times with the Victorian Police Fraud Squad since it was first brought up

“As both MasterCard and industry data reveals no increase in fraud specifically relating to contactless technology, we have asked Victorian Police to clarify the source and nature of their crime statistics relating to contactless fraud,” the statement allegedly read.

Victorian Police Minister Kim Wells said that banks need to do more to ensure security and prevent fraud.

Mr Wells said banks must to the thefts with better way to protected cards once they had been stolen.

This article explains some techniques which may be used to clone or steal information from wireless-enabled cards.