Software giants Microsoft are warning the public, especially the Belgians, against telephone scammers on the pretext of problems with their computer, the site Flanders Info reported on Sunday.

People disguising themselves as Microsoft staff claim there is a computer problem and try to convince the user to start it up, and they next try to install harmful software on his or her computer from a distance, explained Kathleen De Waele of Microsoft.

They later warn people there is something wrong, and that a certain sum needed to be paid for solving the problem.

Taking into account the number of e-mails and phone calls coming in, the fraudsters are "seriously" targeting Belgium, he said.

According to De Waele, the perpetrators speak English and operate from Asia, but use an American telephone number.

For those that do get trapped, Microsoft advises them to hang up their phones and forewarn the federal police.