Mauritanian troops have arrested President Sidi Ould Cheikh Abdallahi, Radio France Internationale (RFI) reported Wednesday.
The president was being held at a building of the presidential guard after being detained at the presidential palace, his daughter was quoted as saying, reported dpa.
Local television and radio stopped reporting.
The reported arrest of the president followed the sacking of high-ranking military officers just before. The prime minister was reportedly also taken into custody.
Mauritania had been regarded as an African democracy model following a string of transparent elections.