Islamabad: The leader of the dreaded Pakistani sectarian militant group, Lashkar-e-Jhangvi (LJ), Malek Ishaq, was killed along with his two sons in a shoot-out in the predawn hours on Wednesday, counter-terrorism officials said.

Six detained suspects, including Ishaq and his sons, were being taken to Muzaffargarh in Punjab provide, to assist in the recovery of arms and explosives, when armed men on motorcycles ambushed the convoy.

The attackers freed Ishaq and his sons but, while fleeing on motorcycles, they were intercepted by a police reinforcement.

In the ensuing encounter a total of 16 militants including the LJ leader his sons Usman and Haq Nawaz were killed, according to police officials.

Six police officers were injured in the shoot-out, which reportedly took place at 3am (local) when the police convoy was returning from Muzaffargarh.

The Counter-Terrorism Department (CTD) described Ishaq’s death as “a big blow” to outlawed militant outfits in southern Punjab.

Ishaq was believed to have been the mastermind behind the 2009 attack on the Sri Lankan cricket team in Lahore, capital of Punjab.

More recently, LJ claimed responsibility for the January 2014 bombing of a bus carrying Shiites, which killed more than 20 people.

In early 2013 it claimed to have carried out a series of bombings in Balochistan that killed more than 150 people, most from Shia Hazara community.

The Al Qaida-linked militant group was outlawed in Pakistan in 2001 and designated a terrorist organisation by the US State Department in 2003.

A spokesman for the CTD reportedly said the militants killed in the shoot-out were linked to the insurgent Tehreek-e-Taliban Pakistan (TTP) and Al Qaida.

Born in 1959 in Punjab’s Rahim Yar Khan district, Malek Ishaq was one of the founding members of the banned sectarian outfit Sipah-e-Sahaba.

Following differences with other SSP leaders, he formed the Lashkar-e-Jhangvi.

Ishaq was taken into custody in 2011, but the Supreme Court ordered his release for lack of evidence.

The militant leader, who was facing more than 100 murder cases and spent long spells in jail, had been in and out of police custody. The Lahore High Court ordered his release several times.

He was often detained and several times kept under house arrest under the Maintenance of Public Order Ordinance and other laws.

Ishaq and his two sons were being kept at the Rahim Yar Khan central jail in Punjab before their death in the shoot-out. Police said he was arrested six days ago on charges of target-killing.