Four people were killed Thursday in a U.S. drone strike in Pakistan's North Waziristan tribal region, the Express Tribune newspaper said, citing an unnamed official.

The unmanned aircraft fired two missiles at a residence in Qutab Khel, 5 kilometers (3 miles) from the district capital of Miransha, the official said.

The identities of those killed in the pre-dawn attack remain unknown, the daily said.

"We can still hear the sound of the drones in the sky," a resident of Qutab Khel told the Express Tribune hours after the explosions.

Around 130 people have died in a score of drone strikes in Pakistan this year, where the U.S. military has mounted no fewer than 30 such attacks in every year since 2007.

Amnesty International issued a report in October denouncing the deaths of Pakistani civilians in the drone strikes.

AI reviewed all 45 known drone strikes that took place in North Waziristan between January 2012 and August 2013, documenting one in October 2012 that killed a 65-year-old woman and another three months earlier that killed 18 laborers, including a teenager.

A recent study by the United Nations said at least 400 civilians have perished in drone strikes in Pakistan, while the Bureau of Investigative Journalism says the death toll could be as high as 926. EFE