President Mamadou Tandja is surrounded by bodyguards in August as he leaves the mayor's office in Niger's capital, Niamey, after casting his vote in a constitutional referendum that kept him in power. (Rebecca Blackwell/Associated Press)

A group of renegade armed soldiers stormed Niger's presidential palace Thursday afternoon in an apparent coup attempt in the West African country's capital of Niamey.

Military music played on state radio later in the evening, the same music that aired after similar coups in the 1990s.

The violence comes months after a referendum passed extending the rule of President Mamadou Tandja beyond the constitutional limit.

Government officials could not be reached for comment and Tandja's whereabouts were unknown. Multiple news agencies reported that sources say Tandja was kidnapped by soldiers, but it is unclear if he is still inside the palace.

Moussa Mounkaila, a palace chauffeur, told The Associated Press gunmen showed up at the palace just as a meeting of government ministers was taking place.

Extraordinary powers

Tandja angered opposition parties in May when he dissolved parliament over his plans to hold the referendum to extend his term.

In June, he invoked extraordinary powers to rule the referendum take place, but a constitutional court overturned the referendum call as illegal.

He later replaced the court with another whose members he chose, clearing the way for the referendum to take place in August.

Niger has had three previous coups, but none since Tandja took power.

The country has also gained notoriety in recent years for kidnappings in the lawless northern deserts.

Two Canadians — UN special envoy Robert Fowler and his assistant Louis Guay — were held for four months by al-Qaeda militants after they were kidnapped on Dec. 14, 2008.

Niger is ranked fifth from last on the UN's worldwide human development index and has an astounding 70 per cent illiteracy rate.

With files from The Associated Press