Islamabad: A suspected suicide bomber, who rammed an explosives-laden vehicle into the motorcade of Pakistan`s one of the most daring counter-terror officials Chaudhry Aslam, has been identified as the son of a local Imam, a media report said on Saturday.

According to initial investigations and evidence collected so far, the police believe that young Naeemullah, who was identified through fingerprints, carried out the deadly attack in Karachi on Thursday, SP Niaz Khosa said.

Some body parts, allegedly of the suspected attacker found at the site of the attack, were sent to the National Database and Registration Authority for identification, the Express Tribune reported.

"(We are) 98 per cent sure that a suicide bomber hit the explosives-laden Suzuki cargo van with Aslam`s Vigo," the report quoted Crime Investigation Department (CID) DIG Zafar Bukhari as saying.

However, police officials insist that the investigation is only in its initial stages and things could change.

Naeemullah was a seminary student and son of Rafiullah, the Imam of Masjid Jamia Sidiqia and Mohtamim (administrator) of Madrassah Siddiqia lil Banat in Karachi`s restive Orangi Town, the report said.

Rafiullah and around half a dozen family members and comrades have been detained by the CID.

According to police officials, the father and son are reportedly members of the Zikria Mehsud group, the Tehrik-e- Taliban Pakistan`s (TTP) Karachi chapter in Sohrab Goth. The police have raided the suspect`s house and detained family members in the past, it said.

The Pakistani Taliban used around 200 kg of explosives for the suicide attack on Aslam, known for his crackdown on the outlawed militant group.

The blast killed Aslam, arguably Pakistan`s best known police-commander who had fearlessly hunted members of the banned group in Karachi despite at least three attacks on him, near Essa Nagri at the Lyari Expressway in Karachi.

Shortly after the attack, Sajjad Mohmand, the Taliban spokesman in Mohmand tribal region, told reporters that his group carried out the "successful" attack to avenge the killing of several Taliban fighters by police.

Aslam had survived numerous assassination attempts in the past. A suicide attack on Aslam`s home in Karachi in 2011 had killed eight persons though he escaped unhurt.