FACTBOX: Mauritania's President Abdallahi held in coup

(Reuters) - Soldiers in Mauritania seized President Sidi Mohamed Ould Cheikh Abdallahi, his prime minister and the interior minister on Wednesday, a presidency official said.

Soldiers gathered at the presidential palace after Abdallahi replaced senior army officers earlier in the day during a political crisis.

Here are some key facts about Abdallahi:

* Mauritanian President Sidi Mohamed Ould Cheikh Abdallahi asked Prime Minister Yahya Ahmed El Waghef to form a new cabinet earlier this month after the premier resigned with his government over a parliamentary revolt.

* This presented Abdallahi with his first major political crisis since he won 2007 elections marking the return of civilian rule to the West Saharan Islamic state.

-- Abdallahi had taken over from a military junta that had ruled since it toppled President Maaouya Ould Sid'Ahmed Taya in a bloodless coup in 2005.

* Abdallahi, who belonged to the white Moorish elite which traditionally ruled the largely desert nation, was born in 1938 and studied in Dakar in Senegal and also Grenoble and Paris, qualifying in Mathematics, Physics and Chemistry.

* In the 1970's he held several ministerial posts including Minister of State for National Economy. In the 1980's he was Minister of Hydraulic and Energy and then Minister of Fisheries and Maritime Economy.