The government of Mauritania was overthrown by an Army coup today.
Army officers announced a new junta was in control of the west African nation which will be led by the head of the presidential guard.
The coup took place after the president and prime minister fired the country's top four military officials.
A brief announcement read over state television said the new "state council" will be led by presidential guard chief general Mohamed Ould Abdel Aziz. It gave no other details.
President Sidi Ould Cheikh Abdallahi was being held by rebel soldiers at the presidential palace in Nouakchott, according to a presidential spokesman. Soldiers also detained Prime Minister Yahya Ould Ahmed Waqef.
State radio and television went off air and witnesses said soldiers were deployed throughout the capital.
United Nations Secretary General Ban Ki-moon today called for the immediate restoration of order. "The Secretary General calls for respect for the rule of law and the immediate restoration of constitutional order in the country," a UN spokeswoman said.
The African Union also condemned the coup and demanded a return to constitutional government. "The African Union ... condemns the coup d'Etat and demands the restoration of constitutional legality," said a statement issued at AU headquarters in the Ethiopian capital Addis Ababa.
The European Commission called for Mr Abdallahi to be restored to power. "The European Commission is very concerned by the situation in Mauritania, which puts into question the remarkable democratic progress in this country," it said in a statement.
EU Aid Commissioner Louis Michel said it could "put into question our policy of cooperation with Mauritania." The EU executive had allocated some €156 million of aid for 2008-2013.
US State Department spokesman Gonzalo Gallegos said the White House condemned the coup “in the strongest possible terms”. He told a news briefing: "We call on the military to release the president and the prime minister and to restore the legitimate constitutional, democratically elected government immediately."
Straddling the western edge of the Sahara desert, Arab-dominated Mauritania, with a population of 3.4 million, has seen more than 10 coups or attempted coups since independence from France in 1960. It became Africa's
newest oil producer after reserves were discovered in 2006.
Mr Abdallahi's civilian government took control from a military junta, which seized power in a 2005 coup and stepped down after 2007 elections. The president had been under pressure for weeks from politicians who accused him of corruption.
The 2005 coup, which saw colonel Ely Ould Mohamed Vall seize power bloodlessly and declare himself president, was widely popular, for many Mauritanians had grown tired of the 21-year rule of former dictator Maaoya Sid'Ahmed Ould Taya.
Al-Qaeda-linked militants have been active in the country, launching sporadic attacks on the military and other targets. Mauritania blamed the 2007 Christmas Eve murders of four French tourists on an Islamic terrorist group.
The attacks prompted French organisers to cancelled this year's Dakar Rally.