US engineer 'seized in Saudi Arabia'

A statement said Mr Johnson was kidnapped on Saturday

The Saudi authorities have launched a search for an American man who has gone missing in Riyadh, amid claims that al-Qaeda has kidnapped him.

If confirmed, it would be the first abduction of an expatriate in fresh violence in the city where three Westerners have been killed in a week.

An alleged al-Qaeda group also claimed the earlier killing of an American.

Saudi police contradicted reports on Sunday that a body thought to be that of a Western man had been found.

Unnamed local officials and diplomats in Riyadh said earlier that a body of someone of Western nationality had been found dumped but the city's police chief said the reports were untrue.

Saudi officials insist there is no security crisis but other nations have advised their citizens to leave the country.

The US embassy has reiterated a warning to Americans in Saudi Arabia to withdraw.

In Britain, the foreign ministry on Sunday authorised non-essential diplomatic staff and their families to return home.

At the same time, British Airways said its flight crews would no longer stay overnight in Saudi Arabia.

'Retribution'

The US state department confirmed that an American man had been reported missing by his family on Saturday.

12 June - US national gunned down in al-Malaz district 8 June - American working for a US defence contractor killed in al-Khalij district 6 June - BBC cameraman killed and BBC reporter seriously injured in al-Suwaydi suburb

"We heard that an Islamic website was making a claim but we have had no direct contacts with any organisations or persons claiming responsibility. We are not releasing the individual's name," spokesman Stuart Patt said.

Various websites said to be used by Islamic militants carried a message by a group calling itself "al-Qaeda Organisation in the Arabian Peninsula" which named the captured American as Paul Marshal Johnson.

The message included photos of various identity documents indicating Mr Johnson is an aeronautical engineer working for Lockheed Martin, a US military manufacturer.

The statement said Mr Johnson, born in 1955, was one of four experts in Saudi Arabia working on developing Apache helicopter systems.

It said the kidnapping was to avenge the mistreatment of Muslims by the US and threatened to treat him in the same way as detainees at US prisons in Baghdad and Guantanamo Bay where abuses have been alleged.

Videoed attack

The website also posted a video allegedly showing the killing of a US security contractor last Tuesday.

An apparently Western man can be seen falling to the ground in front of a garage as two men run towards him amid the sound of gunshots.

Saudi police sealed off the area where Mr Scroggs was shot

The message claimed it was "the murder of the Jewish American Robert Jacob, who worked for the Vinnell espionage firm".

Mr Jacob was shot dead on 8 June, two days after a drive-by shooting on a BBC team left cameraman Simon Cumbers dead and security correspondent Frank Gardner seriously injured.

Another man, American Kenneth Scroggs, was shot dead on Saturday, apparently as he parked his car in the al-Malaz suburb of Riyadh.

Saudi Minister for Islamic Affairs, Saleh bin Abdulaziz al-Shaikh, said that, despite the recent attacks, security in the kingdom "has not reached a stage of crisis".

Attacks on foreigners have been blamed on radical Islamists with links to al-Qaeda.

The kingdom's Islamic militants want to oust the ruling al-Saud family, and to drive out all Westerners, correspondents say.