Eleven Pakistani militants were killed on Saturday after the U.S. launched a drone strike in Pakistan's northwestern tribal region near the Afghanistan border.

Two anonymous Pakistani intelligence officials said that two of the missiles hit a house in the village of Doga Madakhel in Datta Khel, a town in North Waziristan, reports The Guardian. As a result, members of the Punjabi Taliban and Uzbek fighters were killed in the attack. 

The Pakistani military began carrying out a major offensive against militants last month after extremists attacked the country's largests airport in the city of Karachi on June 8.

According to Pakistani officials, most of the causalities were members of Tehrik-e-Taliban Pakistan, an umbrella group that consists of different militant organizations across the tribal areas who believe in overthrowing the Pakistani government and enforcing a hard-line version of Islamic law. The terrorist group has also called for an end to cooperation with the Americans in Afghanistan.

For years, the U.S. government has urged Pakistan to take a hard stance and action against the militant groups operating in North Waziristan. However, Pakistan's Prime Minister Nawaz Sharif resorted to diplomatic means and negotiations with the militants, and pressed the U.S. to refrain from drone warfare during the peace process, reports the The Associated Press.

The U.S. complied until negotiations collapsed after a six-month hiatus, when militants attacked an airport in the city of Karachi on June 8, prompting the government to order military action in North Waziristan.

The Pakistani government still denounces U.S. drone strikes, claiming that they violate the country's sovereignty.

Earlier this week, a U.S. drone strike killed at least 15 militants near the country's border with Afghanistan on Wednesday. The drone fired four missiles at a militant-hideout in the town of in Datta Khel in North Waziristan, two Pakistani officials said.

The military says so far it has killed nearly 500 militants and lost 26 soldiers.