JIDDAH, Saudi Arabia (AP) _ A car bomb apparently exploded outside the heavily guarded U.S. consulate in the port city of Jiddah, sending plumes of smoke into the sky in the latest strike against Western targets in the kingdom. Several people were injured, but no U.S. casualties were reported, officials said.

Witnesses said a car exploded in front of the consulate, and ambulances rushed to the scene. Thick smoke rose from the compound and helicopters hovered overhead. Al-Arabiya satellite television reported that four attackers tried to storm the compound in a car, but that the car exploded in front instead.

A Saudi health official, speaking on condition of anonymity, said several people injured in the blast were taken to a hospital in Jiddah, but none were Americans.

``We can confirm there has been an attack on the consulate,'' U.S. Embassy spokeswoman Carol Kalin said in the capital, Riyadh, adding that no American casualties were reported. ``The incident is still in progress with Saudi emergency forces securing the compound.''

Gunfire was heard nearly 30 minutes after the explosion.

One witness near the scene told The Associated Press smoke was rising from the area and police were keeping cars and traffic away. Other witnesses told the AP gunfire was heard just before the blast.

``As a precaution, we closed our embassy in Riyadh and consulate in Dhahran to the public,'' Kalin said.

Khaled al-Maeena, editor of Arab News located in Jiddah, also said thick smoke was visible from the consulate area and helicopters were flying overhead.

Four men apparently tried to enter the compound, al-Maeena said. They apparently exploded a car in front of the gate. ``The magnitude of this assault on the consulate has taken all Jiddah residents by surprise,'' he said.

The consulate is located in the heart of the city, just a half-mile from the city's Red Sea coastal road. It has been heavily fortified since last year's series of bombings against targets housing foreigners.