RIYADH, Saudi Arabia -- A German man was killed Sunday in a car explosion in the capital Riyadh, German and Saudi officials said.

Police said the victim was a 56-year-old private sector employee. In Berlin, a Foreign Ministry spokesman confirmed the victim was a German national. He did not elaborate.

A preliminary investigation shows the assailant followed the German's car and detonated the explosive by remote control, a police official said.

The explosion took place at 4:26 p.m., and an investigation was continuing, police said, adding it wasn't clear if the car was parked or moving. Police blocked roads leading to Abdel Hamid Al-Kateb St. in the neighborhood of Al-Sulaymanieh where the explosion took place.

There has been a string of car bombings targeting foreigners in the kingdom that Saudi authorities have blamed on disputes between gangs dealing in alcohol.

Concerns about anti-Western sentiments have surfaced in the kingdom since the Sept. 11 attacks and the ensuing war on terrorism, which many Saudis see as an assault on Islam. There have been no reports of violence linked to anti-Western extremists in the kingdom.

Canadian William Sampson and Briton Alexander Mitchell are on death row in Saudi Arabia, awaiting word on their appeal, for convictions in the 2000 bombings. Four other Britons -- James Lee, James Cottle, Les Walker and Peter Brandon and Belgian Raf Schyvens -- are serving prison sentences.