More than 100 left-wing rebels have been killed in clashes with soldiers in the past few days in the Colombian province of Meta, the army has said.

The head of the armed forces, General Jorge Enrique Mora, said his troops had launched an operation against a camp where rebels from the Revolutionary Armed Forces of Colombia (FARC) were sheltering.

There has been no independent confirmation of the numbers of dead.

Correspondents say this is the biggest military operation against the FARC, Colombia's main rebel group, since President Alvaro Uribe came to power last month.

Rebel 'sanctuary'

The clashes took place near La Uribe, 300 km (185 miles) south-east of the capital, Bogota - an area General Mora described as a "sanctuary" for the rebels.

Uribe came to power promising to get tough on rebel insurgents

The military offensive was directed at the group's leader, Henry Castellanos, near the Duda River, Air Force General Edgar Lesmes told the French news agency AFP.

Helicopters that flew over the gorge after the fighting reported the estimated casualties, though General Lesmes admitted the counting methods used were fairly imprecise.

Mr Uribe won the presidency with a promise to get tough on the FARC, and he has secured backing from the United States by presenting himself as the newest and keenest recruit in the war on terrorism.

Three of Colombia's warring factions are on the US terrorism list.

Mr Uribe's government recently suggested that UN mediators should be called in to help bring the country's long-running civil war to an end.

But the FARC rejected the proposal, saying the conflict was "with the Colombian state" not the UN.