RIYADH, Dec 29: A car bomb exploded near Saudi Arabia's interior ministry building in the heart of the capital Riyadh late Wednesday in the latest violence to rock the country, witnesses said.

It was not immediately known if there were any casualties in the blast which occurred at about 8:30pm (1030 PST) after a car tried to crash into an outer gate of the ministry building, triggering a shootout with security guards.

The car then blew up, witnesses said. The interior ministry has been surrounded by tight security over the past few months as the Saudi authorities battle a wave of bombings and shooting attacks in the country blamed on Al Qaeda-linked militants which erupted in May 2003.

Witnesses said the explosion occurred before the vehicle entered a tunnel near the ministry in the district of Al-Maazar, shattering windows in the building. Windows of shops and buildings as far as 700 meters away were also damaged, AFP correspondents said.

Security forces closed off roads leading to the area where both the ministry and the Intercontinental Hotel are located. Scores of ambulances and police cars, sirens wailing and lights flashing, were seen rushing towards the ministry and four ambulances were seen leaving the ministry area, while helicopters hovered overhead.

Dozens of police cars blocked off the site and tried to keep people away. Suspected Al Qaeda militants have killed more than 100 people and wounded hundreds more in Saudi Arabia since launching the spate of attacks. -AFP