KARACHI, Oct 19: Doctors at the Jinnah Postgraduate Medical Centre undertook the facial reconstruction of the bomber whose severed head was found from the site of the twin blasts that rocked a procession of the Pakistan People’s Party and killed more than 130 people on Thursday night.

Investigators also sent the finger-prints obtained from the forearms believed to have been blown off from the body of the suicide bomber to the National Database and Registration Authority.

DIG Investigation Manzoor Mughal told Dawn that the first blast was caused by a Russian-made hand-grenade weighing around 1kg. He said the grenade explosion was aimed at breaching the security cordon around the specially-built bullet-proof vehicle of PPP chairperson Benazir Bhutto and other party leaders. He added that the second blast took place seconds later.

However, a senior police official doubted whether the first blast had been caused by a hand-grenade, arguing that the extent of damage was extraordinary.

CID SP (operations) Raja Umar Khattab told Dawn that he had recommended DNA tests on body parts obtained from the site of the blasts.

A high-ranking police official — part of Ms Benazir’s security detail — told Dawn that the bullet-proof vehicle of the PPP leader was stationary when the suicide bomber struck. He said that two security vehicles fitted with jammers moved ahead of and behind Ms Bhutto’s truck, which was flanked by four to five police vans at a time.

He said the first blast took place on the right side of the truck. He added that the second explosion, which wrought greater devastation, took place on the left side of the truck. He said Ms Bhutto was immediately whisked away in a bullet-proof jeep.

The police official said one vehicle fitted with the jammer was extensively damaged in the second explosion. He conceded that the two jammers had broken down primarily because charged PPP activists had knocked over their antenna, installed atop the cars in which they were fitted.

But, he said, jammers could not have prevented Thursday’s explosions because they had not been detonated by remote-controlled device. The explosives were manually detonated by the suicide attacker.

Five policemen sitting in the van close to the truck died on the spot while 27 other policemen were injured. They were part of Ms Bhutto’s security cordon.

The police official said PPP activists gave the impression that the first blast was a tyre burst or an explosion in a pole-mounted transformer. The second explosion came as a rude shock.

He said SP Fareed Jan Sarhandi, who was sitting in the vehicle fitted with a jammer vehicle in front of Ms Benazir’s truck, ran back to evacuate the PPP leader to safety as part of the contingency plan.

Another high-ranking investigator told Dawn that RDX, which is widely used in military and industrial applications, was employed in the suicide attack on the PPP leader.

He said the explosives weighed around 12kg. He added that the explosives contained ball-bearings and pellets which killed a large number of people and also left nearby vehicles pock-marked.