Northern Ireland companies are losing thousands of pounds due to a phone scam, it's been warned.
Independent business telecoms company Rainbow Communications, which carries out fraud checks on phone lines, is warning companies to be extra vigilant against criminals breaking into phone lines remotely and racking up huge bills.
David Beatty, head of Systems and data sales at Rainbow Communications, said one Belfast services firm lost £10,000 in just one weekend while one retail outlet in North Down was scammed to the tune of £3,000.
Figures show that global losses due to this type of fraudulent activity amount to tens of billions every year.
"We are all too aware of the term 'phone hacking' in the media, but this type of phone hacking is a real and serious concern for businesses in Northern Ireland," he said
"Fraudsters are making thousands of international or premium rate calls resulting in substantial costs at the expense of the unsuspecting company.
"It is the business that is solely responsible for the fraudulent call charges so it really can have a detrimental effect on any firm in Northern Ireland."
"There have been cases of businesses losing tens of thousands of pounds."
He has urged firms here to take steps to prevent the fraudsters, including restricting the numbers that employees can dial and barring all unnecessary call destinations such as international or premium rate numbers.
Mr Beatty said that companies should restrict after hours, weekend and holiday calling, remove all unnecessary personnel who have remote access to systems and review call logging reports regularly.
He also urged people to be vigilant against people posing as a company employee and asking to be connected to a switchboard operator to get an outgoing line.