With Al-Qaida in the Arabian Peninsula (AQAP) growing in strength, Washington is preparing to evacuate its ambassador from Yemen, the London Telegraph reported Wednesday. The British Embassy and many other Western missions have drastically reduced their presence in the capital Sana'a because of the danger of attack.

"Yemen is standing on the edge of a precipice," a Western source said. "The rule of law has almost totally collapsed and AQAP can maneuver with unimpeded and unprecedented freedom. The current risk is as high as it could be."

Non-essential diplomats were ordered to leave Yemen Thursday, after an explosion at a weapons storage center killed 28 people

More than 100 people have died since Sunday in fighting between troops loyal to Yemeni President Ali Abdullah Saleh, who has ruled Yemen for 32 years, and Sadiq al-Ahmar, one of the president's most bitter tribal opponents.

The security situation took a turn for the worse on Tuesday, with troops loyal to Saleh launching attacks on Yemeni troops who had defected from the military and were trying to protect anti-government demonstrators. The Telegraph described a chaotic situation in which thousands of people fled Sana'a as plainclothes gunmen roamed the streets firing at will, while regime foes attempted to storm the interior ministry and occupied the national airline headquarters.

AQAP has been a major beneficiary of the mounting chaos in Yemen and the political turmoil surrounding Saleh, once an important U.S. ally in the war against AQAP. The New York Times reported last month that counterterrorism operations in Yemen "have ground to a halt" and that the group had become able "to operate more freely inside the country and to increase plotting for possible attacks against Europe and the United States."

AQAP has been linked to the Fort Hood massacre, the underwear bomber's attempted suicide bombing of a plane near Detroit, and the attempted bombing of two air cargo flights last October.