Islamabad, Jan 11 (IANS): A man on death row in Pakistan, convicted of killing the Imambargah's former caretaker, is being investigated for his possible link with Friday's Rawalpindi blast, which left eight people killed and 20 injured.

Pakistan Taliban's Jamaatul Ahrar faction has claimed responsibility for the attack.

But police officer Akhtar Umar Hayat Laleka told media they are exploring links between Friday's bombing of the Imambargah in Rawalpindi, the twin city of Islamabad, and Hafiz Mohammad Nawaz, now facing execution for the 1999 killing of Aun Mohammad Rizvi, the then caretaker of the Imambargah.

Hafiz Mohammad Nawaz, who was awarded capital punishment for the killing of Rizvi, also a former controller at Pakistan Television, is nephew of Riaz Basra, a prominent leader of Lashkar-e-Jhangvi (LJ), a banned terrorist group in Pakistan, Dawn reported.

"If necessary, police will interrogate the convict. However, a few suspects connected with the bombing are in police custody," the officer added.

Also, the bomb disposal experts have disputed witnesses' claims that the bombing was a suicide attack. They say there was no doubt that a device containing two kg high-intensity explosives was planted near Imambargah's entrance.

"Yes, it was a planted device, but we are not sure whether it was a timed or a remote-controlled device," a bomb disposal squad member said.

"There were some pieces of the metal which was used to make the bomb. These have strengthened our report," he said, adding that had it been a suicide attack, the bomber's body parts and splashes of blood would have been found.