SANAA: The United Nations closed its offices in the Yemeni capital on Thursday over fears of possible car bomb attacks but Western embassies remained open.
Most shops in Sanaa were shuttered and little traffic ventured out onto the streets as rumours swirled among the city's residents of the risk of an imminent attack.
The American and Turkish schools were also closed.
Security forces have been on high alert in the capital since a brazen daylight attack on the defence ministry's sprawling headquarters on December 5 killed 56 people, among them expatriate medical staff.
Information gleaned during the investigation into that attack, which was claimed by Al-Qaeda, led to the discovery of two cars packed with explosives and a massive search for five more suspected to be still inside Sanaa.
A UN source said Wednesday that a warning from Yemeni authorities of a possible attack in Hada, the south Sanaa neighbourhood where UN offices are located, had triggered the closure order.
"Staff of the UN mission and UN agencies have received instructions not to turn up for work on Thursday," the source said.
The source said it was a "precautionary measure following advice from Yemeni security authorities". The guidance warned of the "risk of possible acts of terrorism in certain places, particularly in Hada."
But a senior Yemeni security official said no warning had been issued through authorised channels and dismissed the alleged guidance given to the UN as part of "a campaign of rumours aimed at spreading fear in the country."
"Western embassy security chiefs met with Yemeni officials on Wednesday and no attack warnings were issued," the official told AFP, speaking on the condition of anonymity.
The US embassy said it remained open and referred all questions about security to the Yemeni government.
The British and French embassies were also operating normally.
In August, a security alert originating in Yemen prompted an unprecedented closure of American embassies across and beyond the Middle East, which was mirrored by the British and French missions in Sanaa.