The Pakistani city of Lahore saw one of its largest demonstrations ever Dec. 18 as tens of thousands of people protested against the U.S.-led NATO airstrikes that killed 24 Pakistani soldiers on Nov. 26. The attack was just the latest incident for the country that has also seen hundreds of civilians killed by unmanned predator drones.

Widespread public opposition to the U.S. has pressured the Pakistani government to take a firm response, and the reaction has been decisive. Accusing the U.S.-led forces of deliberately attacking its soldiers, Pakistan promptly denied NATO supply convoys critical access to Afghanistan, ordered the U.S. to leave an airbase that has allegedly been used by CIA drone flights and boycotted a Bonn conference that aimed to determine the future of Afghanistan.

The Pentagon has expressed “regret” over the killings, saying that a lack of trust between the U.S. and Pakistan was a key factor leading to the attack. The U.S. government has refused Pakistan’s call for an official apology.