Two suspected members of the militant Islamic State group allegedly linked to the 2013 abduction of former prime minister Yousuf Raza Gilani's son, Ali Haider Gilani, were killed in a pre-dawn raid on a 'militant hideout' in Faisalabad on Tuesday, a Punjab Counter-Terrorism Department (CTD) official said.

CTD official Rai Tahir identified the two militants as Adeel Hafeez and Usman Haroon. He said both were killed during an intense shootout in the raid conducting by security officials.

Tahir said officials had, in the past, foiled other attacks the pair had plotted, adding that they were also behind the killing of two intelligence officials in recent years as well as other high-profile crimes.

The two militants were also linked to the 2011 Al Qaeda abduction of an American development worker, Warren Weinstein, the official said. Weinstein, who was taken from Lahore, was accidentally killed in a United States drone strike in 2015 on the Afghanistan-Pakistan border. He provided no specific information about the role the two had in Weinstein's case.

The American worker's accidental death was announced by Washington in 2015. President Barack Obama at the time said he took full responsibility for US counter-terror missions and offered his condolences to families of the hostages.

After the Sept 11 attacks in the United States, Washington aggressively targeted militant hideouts in neighbouring Afghanistan and Pakistan's tribal regions, killing local and foreign militants. Pakistan considers US drone strikes a violation of its sovereignty, while the US accuses Pakistan of providing safe havens for militants. Pakistan has always denied the charge, saying it acts against militants without discrimination.

Many former Al Qaeda militants are thought to have joined the regional IS affiliate, which emerged a few years ago, around the time the group was at the height of its caliphate in Iraq and Syria. IS has since lost nearly all the territory it once controlled in the two Middle Eastern countries.