WASHINGTON - A US airstrike earlier this month in southeast Afghanistan killed the man behind the Marriott hotel attack in Islamabad and an assault on Sri Lankan cricket team, the Pentagon said late Saturday.

The strike in Paktia province, conducted March 19, killed Al-Qaeda operative Qari Yasin, according to a statement.

In September 2008, the suicide truck bombing at the Marriott motel in Islamabad killed more than 50 people, including two US servicemembers.

Yasin was also behind other attacks, the Pentagon said, including an attack on the Sri Lankan cricket team in March 2009. That attack killed eight people, including six police officers and two civilians.

His attack in Lahore led to Pakistan’s isolation in the world cricketing community, as a host. It hasn’t had any international side since, and plays others on their home ground or at third-party venues.

"The death of Qari Yasin is evidence that terrorists who defame Islam and deliberately target innocent people will not escape justice," Defence Secretary Jim Mattis said in the statement.

The killing of Yasin validates Pakistan's stand that its militant enemies have found sanctuaries in Afghanistan.

Kabul-Islamabad relations deteriorated earlier this year after a series of attacks in Pakistan that killed 125 people led Islamabad to close its border with Afghanistan for more than one month.

Agencies add: According to AFP, Qari Yasin, who went by several aliases including Ustad Aslam, was also a member of the Tehrik-e-Taliban Pakistan group (Pakistani Taliban).

According to official Pakistani 'Most Wanted' lists he was also behind failed attempts to kill former President Pervez Musharraf in 2003 and former Prime Minister Shaukat Aziz in 2004.

The Pentagon described him as being a native of Balochistan, though Pakistani records said he hailed from Punjab.

Security analyst Amir Rana said Yasin was the latest in a series of Pakistani militant fugitives to have been killed across the border in Afghanistan, including Qari Saifullah Akhtar, a former close associate of Mullah Omar, who died in a clash with Afghan security forces in January.

"He was once a senior figure and one of the Pakistani Taliban's few non-Pashtun leaders," said Rana, but added that Yasin had fallen inactive in recent years after fleeing to Afghanistan.

Pakistan and Afghanistan have long accused each other of habouring militants who carry out attacks in each others' countries.

Taliban fighters on Thursday captured Afghanistan's strategic southern district of Sangin, where US and British forces had suffered heavy casualties before it was handed over to Afghan personnel.

The Taliban effectively control or contest 10 of 14 districts in Helmand, the deadliest province for British and US troops over the past decade, blighted by a huge opium harvest that helps fund the insurgency.

The Pentagon has said it would deploy some 300 Marines this spring to Helmand, where American forces had engaged in heated combat until they pulled out in 2014.

The Marines will assist a NATO-led mission to train Afghan forces, in the latest sign that foreign forces are increasingly being drawn back into the mounting conflict.

Reuters adds: Pakistan's Counter-Terrorism Department had offered a bounty of two million rupees for Qari Yasin.