by JEREMY CAMPBELL, Evening Standard

President George Bush has launched an investigation into what appears to be a systematic disabling of White House equipment by outgoing members of Bill Clinton's staff, and obscene messages left for the new administration.

The inquiry, which could result in prosecution, was prompted by what internet journalist Matt Drudge called "acts of vandalism and destruction of federal property" and widespread sabotage of White House office equipment.

Telephone lines have been cut, voice-mail messages changed to scatological, lewd greetings. One Bush staffer's grandmother telephoned his office from the Midwest and was "horrified" by what she heard on his message machine.

Many telephone lines were switched to the wrong offices. Desks were turned upside down and rubbish scattered everywhere.

Filing cabinets were glued shut, pornographic pictures inserted into computer printers, together with obscene slogans. In one office hallway, lewd graffiti had been written with a Magic Marker.

Harriet Miers, assistant to President Bush, will head the investigation and will consider legal action against individuals for theft. White House aides are providing her with names of Clinton staffers who occupied offices in which the sabotage is particularly blatant.

Video films of the ransacked quarters and damaged equipment are being prepared, as well as taped inter-views with key people.

Offices in the vice president's quarters next to the White House were also found in a "complete shambles". Tipper Gore, wife of outgoing Vice President Al Gore said she was "mortified" and apologised to incoming Vice-President Dick Cheney.

Earlier this week it was learned that many computer keyboards in the White House are missing the letter "W" which is President Bush's middle initial. He is often known by that alone. It was the extent and organised nature of the mischief that apparently persuaded the incoming Bush staffers that it was more than just a prank.

"There are dozens, if not hundreds, of keyboards with these missing keys," a White House aide said. "In some cases the 'W' is marked out, but the most prevalent example is the key being removed.

"In some cases the 'W' keys have been taped on top of the doorways, which are 12 feet tall. In other cases, they were glued on with Superglue, right way up or upside down."

The vandalism occurred in "any number" of different offices, the aide said. "It has the technical and computer support people very busy. They already have quite a lot to do. I don't believe they expected to be coping with this as well."

The new White House staff have been told to keep quiet for now about the extent of the damage, Mr Drudge said. That means the worst may not be known yet. Prosecutions are considered likely.