A five-member squad of militants was assigned the task of targeting slain former premier Benazir Bhutto [Images] because she might have allowed foreign forces to act against the Mujahideen and Taliban if she came to power in Pakistan's general election, a top police official said on Wednesday.

This was disclosed by two men, Hasnain Gul and Rafaqat, who were arrested for alleged involvement in Bhutto's assassination, said Additional Inspector General of Police Abdul Majeed, who is heading the special police team probing the opposition leader's killing.

"The motive behind the attack was that Mohtarma Bhutto was coming back to Pakistan with the backing of foreign powers, and if she won the polls, she may have allowed foreign forces to take action against the Mujahideen and Taliban," Majeed said.

Addressing a press conference late on Wednesday night after Gul and Rafaqat recorded their confessional statements before a judicial magistrate in Rawalpindi, Majeed said Bhutto's assassination was planned in November 2007.

Majeed identified the two suicide attackers who were part of the five-member squad as Bilal alias Saeed and Ikramullah.

Bilal was the man who fired shots at Bhutto after she addressed an election rally at Liaquat Bagh in Rawalpindi on December 27 and then blew himself up near her armoured car, he said.

Ikramullah, who was also wearing a suicide jacket, was to have targeted Bhutto if she survived the first blast.

After the attack on her, Ikramullah spent the night in Rawalpindi and travelled to the militant stronghold of Waziristan the next day. Majeed said Ikramullah was currently absconding.

Majeed did not name the fifth member of the militant squad, saying that disclosing his identity could harm the investigation.

He said Gul, Rafaqat and the fifth man entered the venue of Bhutto's rally and even tried to get Bilal inside so that he could carry out the suicide bombing inside Liaquat Bagh.

"But Bilal was unable to enter Liaquat Bagh due to the rush," he said.

Gul provided suicide jackets to both Bilal and Ikramullah. He also gave Bilal the 30-bore pistol that was used to fire several shots at Bhutto, Majeed said.

Rafaqat and Gul also played a crucial role in helping Bilal and Ikramullah to carry out a survey of Liaquat Bagh after the suicide bombers came to Rawalpindi on December 26.

The squad used Rafaqat's taxi to travel around the city.

"We arrested Gul and Rafaqat after a great deal of effort. We are continuing the probe and we will get to the mastermind," Majeed said, refusing to give further details.

TV channels also reported that Gul and Rafaqat had said in their confessional statement that Bhutto was assassinated in retaliation for 2007's military operation against militants holed up in the Lal Masjid.

The two men, who were arrested from different areas of Rawalpindi on February 7, were produced before the magistrate under tight security.

Gul said Bilal's brother was among those killed in the Lal Masjid operation. Reports said that Gul's brother too had died in the same operation. Over 100 people were killed when troops stormed the Lal Masjid.

Gul, who hails from a village near Hasanabdal town in Punjab province, said the teacher at his seminary used to urge the students to avenge those who were killed in the Lal Masjid.

Rafaqat and Gul also confessed to helping two other suicide bombers who carried out attacks in Rawalpindi, including the bombing of a military bus near Royal Artillery Bazar on February 4 that killed 10 people.

They also said that the militants had planned to target former federal minister Sheikh Rashid Ahmed, who lives in Rawalpindi.

Two other suspects linked to the Bhutto assassination -- 15-year-old Aitezaz Shah and Sher Zaman, who were arrested in Dera Ismail Khan -- are also in the custody of police in Rawalpindi.

Bhutto's Pakistan People's Party has said it is not satisfied with the probe being conducted by Pakistani police into the assassination and demanded a UN-led inquiry to expose the "hidden hands" that planned and sponsored her killing.