Jan 26, 2009, 20:36 GMT
Sana'a, Yemen - Policemen manning a barricade outside the US embassy in Sana'a on Monday opened fire at a car Monday, but there were no casualties reported, an interior ministry official confirmed.
'Policemen fired warning shots after a car passed the blockade outside the embassy,' the official, who asked not to be named, told Deutsche Presse-Agentur dpa.
The official said three people were in the car, and an initial investigation revealed that the vehicle did not intentionally pass the police barrier.
A security source had said earlier that police chased the car after gunmen in the vehicle fired at the barricade and fled.
The incident took place hours after the embassy said it had received a threat of 'possible attack' against its compound and asked US citizens in Yemen to exercise caution.
'The US embassy has received a threat against the embassy compound regarding a possible attack which could take place in the foreseeable future,' the embassy said on its website.
'US citizens in Yemen are advised to exercise caution and take prudent security measures in all areas frequented by Westerners,' the message said.
It asked Americans to maintain a 'high level of vigilance,' avoid crowds and keep a low profile.
Witnesses said police closed a street near the embassy in eastern Sana'a and dozens of police personnel were deployed around the compound.
The reported threat comes three days after the leader of al-Qaeda in Yemen, Nasser al-Waheishi alias Abu Bassir, threatened to carry out attacks against US and Western interests in the Arabian Peninsula.
'We will cut supply lines of the US forces in the Arabian Peninsula and attack Westerners and Western interests until America stops its support to the Jews,' al-Waheishi said in a rare video posted on Islamist web sites on Friday.
Last September, the US embassy was hit by a suicide car bombing, the deadliest attack on a foreign embassy in Yemen since the October 2000 bombing of the warship USS Cole in the southern Yemen port of Aden, which left 17 sailors dead and 32 wounded.
Al-Qaeda claimed responsibility for the embassy attack that left 18 people dead, including six militants.
A mortar attack last March targeted the embassy, injuring three police officers and four girls in a neighbouring school.
A similar attack targeted a residential compound housing US and Western citizens in April - no one was hurt. Al-Qaeda claimed responsibility for both attacks.
After the September 11, 2001, terrorist attacks in the US, Yemen allied itself with the US-led 'war on terror' and pursued suspected members of al-Qaeda, putting scores of them on trial.
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