Students gather at the site of a suspected US drone strike on an Islamic seminary in Hangu district, bordering North Waziristan, November 21, 2013. [Photo/Agencies]

PESHAWAR, Pakistan/KABUL - A suspected US drone strike on an Islamic seminary in Pakistan killed a senior member of the Taliban-linked Haqqani network early on Thursday, Pakistani and Afghan sources said.

It was the first drone strike in the nuclear-armed South Asian nation since Pakistani Taliban chief Hakimullah Mehsud was killed on November 1 in an attack that sparked a fierce power struggle within the fragmented insurgency.

Maulvi Ahmad Jan, an adviser to Sirajuddin Haqqani, the feared head of the Taliban-linked Haqqani network, was in the madrassa when at least three rockets hit his room in the Hangu district of Khyber Pakhtunkhwa just before sunrise.

"Yes it's true, we lost another valuable figure this morning," a senior Haqqani official told Reuters.

A Pakistani intelligence source said that Sirajuddin Haqqani himself was spotted at the same seminary just two days earlier.

The group is one of the main enemies of US-led forces in neighboring Afghanistan, frequently launching attacks on foreign troops from mountainous hideouts in Pakistan's lawless North Waziristan region.

But it has been under considerable strain this month since its chief financier, Nasiruddin Haqqani, was shot dead in Islamabad on November 11. No one claimed responsibility for that shooting.

A source with Afghanistan's National Directorate of Security intelligence agency confirmed Jan's death. At least four other people also died in the attack but dozens of students sleeping in other rooms were unhurt, police and militant sources said.

Washington has long urged Islamabad to crack down on the group. Nasiruddin's father was once an ally of the United States during the rebellion in Afghanistan against the Soviets.

Pakistan publicly opposes US drone strikes, saying they kill too many civilians and violate its sovereignty, although in private officials admit the government broadly supports them.

Thursday's missiles hit only two of the nine rooms in the seminary where Jan was staying with several other militants.

"Only the two rooms where Maulvi Ahmad Jan and other Afghan Taliban leaders were staying were hit by the drone. The remaining seven rooms remained intact," a local resident said.

Most drone strikes occur in the lawless North Waziristan region where Taliban insurgents are holed up, and are rare in densely populated places such as Khyber Pakhtunkhwa.

The attack took place a day after Pakistan's foreign policy chief Sartaj Aziz was quoted as saying the United States had promised not to conduct drone strikes while the government tries to engage the Taliban in peace talks.

The United States has not commented on Aziz's remarks.