WASHINGTON - The US State Department said on Wednesday that it has ordered a further reduction in staffing of the US embassy in Syria due to security concerns.

The agency warned US citizens against all travel to the Arab nation, saying it "has decided to further reduce the number of employees present in Damascus, and has ordered a number of employees to depart Syria as soon as possible."

In an updated travel warning posted on its website, the agency advised US citizens currently in Syria to leave immediately while commercial transportation is available, while those who must stay behind were cautioned against nonessential travel within the country.

It said that since March 2011, demonstrations throughout Syria have been "violently suppressed" by Syrian security forces, resulting in thousands of deaths, injuries and detentions.

"In recent days, violence has escalated in cities around Syria, including the capital, Damascus," the traveling warning said. "Demonstrations, and violent government reactions to them, can occur with little or no warning anytime and anywhere."

On July 11, 2011, the US and French embassies in Damascus were attacked by people participating in a pro-government demonstration, as the two countries' ambassadors visited restive areas to show support for anti-government protesters.

US Ambassador Robert Ford was called back on October 24 due to threats against his safety, but returned on December 6. And in October, the State Department ordered family members of embassy staff to leave and restricted staffing.