TANK, Pakistan — The Pakistani military blocked a convoy carrying thousands of Pakistanis and a small contingent of US antiwar activists from entering a lawless tribal region along the border with Afghanistan on Sunday to protest American drone strikes.

The group, led by cricket-star-turned-politician Imran Khan and his political party, was turned back a few miles from the border of South Waziristan. After an hour of fruitless negotiations, Khan announced that the caravan would backtrack to the city of Tank, about 9 miles away. There, he delivered a speech to the crowd of about 10,000.

Khan has harshly criticized the Pakistani government’s cooperation with Washington in the fight against Islamist militants.

He has been especially outspoken against US drone strikes targeting militants and has argued that Islamabad’s alliance with Washington is the main reason Pakistan is facing a homegrown Taliban insurgency. He has suggested before that militant activity in Pakistan’s tribal areas will dissipate when the United States ends the war across the border in Afghanistan.

“We want to give a message to America that the more you carry out drone attacks, the more people will hate you,” Khan told the crowd.

The anti-American sentiment, always high in Pakistan, was evident in the crowd that waved banners saying “Down with America,” and “The friend of America is the traitor of the nation.”

Pakistan’s tribal regions, such as North and South Waziristan, border Afghanistan and serve as bases for militant groups such as the Taliban to stage raids across the border into Afghanistan.

About three dozen Americans from the US-based antiwar group Codepink joined Khan for the march. The American protesters say the US drone strikes, contrary to the assertions of American officials, have terrorized peaceful tribes living along the border.