Bamako: Coup leaders in Mali on Thursday ordered all borders closed after taking over key buildings in Bamako and ousting President Amadou Toumani Toure overnight, sparking international concern and condemnation.

The band of mutineers, calling themselves the National Committee for the Establishment of Democracy, said their move was prompted by government's "inability" to put down a Tuareg-led insurrection in the north.

Sporadic gunfire rang out in the capital as condemnation poured in from western powers and the African Union urged "the mutineers immediately to put an end" to the country's first coup in 21 years.

France suspended cooperation with its former colony, urging soldiers not to harm Toure who was at a military camp under protection from his elite paratrooper guard. It remained unclear how tight the junta's grip on power was.

Washington, which has repeatedly voiced fears parts of Mali and neighbouring countries were becoming a safe haven for jihadi extremists, called "for the immediate restoration of constitutional rule."

While politically stable, smouldering troubles in Mali's north where light-skinned Tuareg tribes have long felt ignored by a southern government and Al-Qaeda has taken deep root, turned the region into a tinderbox.

This was ignited when the demise of Muammar Gaddafi sparked the return of hundreds of heavily-armed Tuareg rebels who had fought for him in Libya and were ready to take up a decades-long struggle for independence.

What began as a mutiny over the government's response to the rekindled Tuareg insurrection in the north yesterday turned into a full-blown coup as soldiers seized control of the Presidential palace and the state broadcaster.

A few dozen soldiers appeared on the screens after hours of music videos played in a loop. They appeared to be largely rank-and-file green-beret soldiers, with only two officers present.