Kabul, Afghanistan ? The U.S.-led coalition said Sunday it must continue its massive anti-Taliban offensive in southern Afghanistan until local authorities gain control of the insurgent-dominated region.

More than 10,000 soldiers have fanned out across southern mountain ranges, desert plains and opium fields to crush the Taliban in Operation Mountain Thrust, the largest military operation in Afghanistan since the U.S.-led invasion that toppled the Taliban regime in late 2001.

Authorities said more than 70 Taliban were killed in 24 hours of violence in southern Helmand province.

Afghan President Hamid Karzai has criticized the coalition for killing too many civilians.