Philippine investigators said yesterday that they will charge Onel de Guzman with "fraud and malicious mischief" over the worm virus that caused billions of pounds worth of damage to business computers last month.

The 24-year-old student had already admitted that he may have "accidentally" unleashed the virus from his Manila apartment, but denied being its author.

According to reports today, however, officers at The Philippine National Bureau of Investigation say de Guzman is "the one responsible" and that they will file charges as soon as their lawyers review a report prepared by investigators.

But experts have previously warned that Philippine law doesn't specifically cover computer crime and that it may be hard for prosecutors to gain a conviction.

If found guilty, de Guzman could face six years in prison, but he is unlikely to be extradited to the US as the charges may not be deemed of sufficient gravity to warrant such a move.