(CNN) -- International and Afghan security forces wounded and captured a Taliban district chief and killed a "large number" of insurgents in a four-hour firefight, NATO's International Security Assistance Force said in a statement Thursday.
The battle took place in a compound outside a village in the Baghran district of Afghanistan's Helmand province after insurgents opened fire on security forces with rocket-propelled grenades and machine guns, ISAF said.
No security force members or civilians were killed or wounded in the fighting, but a "large number of insurgents" died, ISAF said, without providing specific numbers.
"Dozens of automatic weapons, RPG launchers and rounds, a machine gun, grenades, and ammunition were discovered along with 20 pounds of wet opium" after the fighting, the statement said.
"This joint force operation dealt another significant blow to the Taliban network," said Col. William Maxwell, ISAF Joint Command Combined Joint Operations Center director. "These joint efforts are key to further establishing peace in the region."
NATO-led forces have been waging an offensive against the Taliban in southern Afghanistan.
Dubbed Operation Moshtarak, the offensive was launched in February by an international coalition of 15,000 troops including Afghans, Americans, Britons, Canadians, Danes and Estonians.
The Taliban had set up a shadow government in Helmand province's Marjah region, long a bastion of pro-Taliban sentiment.
It is a key area in Afghanistan's heroin trade and full of the opium used to fund the insurgency.