The Pakistan police investigating the suicide attack that killed 16 commandos of an elite counter-terrorism force at a high-security army camp in Tarbela on Thursday have found the head of the bomber.

The suicide bomber blew himself up at the camp in north-western Pakistan, killing many security personnel, most of them officers.

The Special Services Group were having dinner when the bomber blew himself up at their mess.

Local TV reports said the bomber targeted the elite SSG unit which had taken part in the Lal Masjid operations on July 23 in which scores of armed militants were killed.

Geo TV reported that the police were allowed by the army today to enter the site of the blast for the first time as part of their investigation.

The army is also holding its own investigation, and reports said a suspect was also taken into custody yesterday.

A guard, Ismail, told the police that he saw a bearded youth, wearing white clothes and a white cap, moving towards the soldiers' mess on his cycle.

Ismail said he thought the boy was taking food for the soldiers but when he entered the mess there was a huge blast, which destroyed the main hall. The body of the bomber was divided into two parts, the police said.

Pakistan is witnessing increasing incidents of violence since troops stormed Islamabad's Red Mosque in July and the Taliban scrapped the agreement with the government in the restive North Waziristan tribal region.

Two weeks back, two suicide bombings ripped through a military bus carrying defence ministry employees through a busy market near Pakistan's military headquarters in the garrison town of Rawalpindi killing 25 people and injuring 68 others.