* Britain withdraws all workers from Sana'a embassy * Ministry releases names of 25 terrorists on the lose * UN refugee agency boosts security amid Qaeda alert SANA'A – The United States told its citizens in Yemen on Tuesday to leave immediately and ordered the evacuation of non-essential US government staff because of the threat of terrorist attacks. Britain also said that it had withdrawn all staff from its embassy in Sana'a and extended the closure of the mission until further notice. “Due to increased security concerns, all staff in the British Embassy have been temporarily withdrawn and the Embassy will remain closed until staff are able to return,” the Foreign Office said on its website. “There is a very high threat of kidnap from armed tribes, criminals and terrorists. Be particularly vigilant during Ramadan, when tensions could be heightened,” it said. The UN refugee agency said Tuesday it had boosted security in Yemen. “We're there, but we're operating under extreme caution, and certain restrictions,” UNHCR spokeswoman Melissa Fleming told reporters. The US State Department post on its website said: “The Department urges US citizens to defer travel to Yemen and those US citizens currently living in Yemen to depart immediately.” “On August 6, 2013, the Department of State ordered the departure of non-emergency US government personnel from Yemen due to the continued potential for terrorist attacks,” it added. Yemeni Foreign Minister Abu-Bakr Al-Qirbi criticised the measures but said they would not affect relations with the United States. “Unfortunately, these measures, although they are taken to protect their citizens, in reality they serve the goals that the terrorist elements are seeking to achieve,” Qirbi said. The country's Supreme Security Committee earlier issued a statement saying it had received information that Al-Qaeda militants were plotting to carry out attacks on public facilities during the Eid Al-Fitr holiday this week. The committee also published a list of 25 senior Al-Qaeda militants it said were being sought by security forces and offered a bounty of 5 million Yemeni riyals ($23,000) for information leading to their capture. “Information has become available that terrorist elements of the Al-Qaeda network were planning to carry out terrorist acts targeting public installations and facilities, especially in a number of Yemeni provinces, in the latter days of the holy month of Ramadan and during the Eid Al-Fitr holiday,” it said. It listed some allegedly senior figures in the branch, including Ibrahim Mohammed Al-Rubaish and Ibrahim Hassan Al-Assiri. Al-Rubaish was released from Guantanamo in 2006 and is believed to have played significant roles in Al-Qaeda's expanding offshoot in Yemen. He is a theological adviser to the group and his writings and sermons are prominent in the group's literature. Earlier on Tuesday, a US drone fired five missiles at a car travelling in the central Maarib province killing all four of its occupants, local tribal leaders said. The New York Times reported on Monday that the closure of the embassies was the result of intercepted electronic communications between Ayman Al-Zawahri, who replaced Osama Bin Laden as head of Al-Qaeda, and Nasser Al-Wuhaishi, the head of AQAP. US sources said that while some type of message between Zawahri and AQAP was intercepted recently, there were also other streams of intelligence that contributed to the security alert, which was prompted by a threat from AQAP. – Agencies