The report accuses the slain chief of Tehrik-i-Taliban Pakistan, Baitullah Mehsud, of masterminding the murder.

Anti-Terrorism Court-I Special Judge Malik Mohammad Akram Awan adjourned hearing till June 12 when the five arrested accused, Aitzaz Shah, Sher Zaman, Abdul Rasheed, Hasnain Gul and Rafaqat Hussain, will be formally charged.

The FIA said in the report that a joint team was continuing its investigation into the hosing down of the crime scene, negligence, inadequate security measures and failure to conduct post-mortem on the body of Ms Bhutto. It will submit a report after completing the probe.

The FIA launched a re-investigation into the assassination in August last year.

The FIA said it had gathered more evidence against the accused and those declared offenders. It said that DNA tests first conducted by the Armed Forces Institute of Pathology and later by an FBI laboratory in the United States on the limbs of two alleged suicide bombers — Saeed alias Bilal and Ikramullah — and on their articles found in the house of Hasnain Gul confirmed that the two lived with Gul in Rawalpindi.

Accepting the findings of Punjab police, the FIA said the record of a call made by arrested accused and data of two numbers involved in conversation about the success of Dec 27, 2007, suicide attack confirmed the alleged role of the accused.

The report said that certain students of Madressah Darul Uloom Haqqania Akora Khattak in Nowshera had been founded involved in the assassination of the former prime minister.

About the alleged negligence of police officers on duty, the FIA said it had carefully examined statements of the officials concerned and witnesses and also scrutinised the relevant record.

Members of the joint investigation team have found Rawalpindi police officers responsible for security breach, including the absence of police escort officer of Benazir on her departure form Liaquat Bagh, and a series of lapses, including the destruction of vital evidence and failure to conduct the post-mortem.

The investigators were yet to fix responsibility because of conflicting statements of the police officers concerned. The FIA said that a final report would be submitted after completion of these aspects of the investigation.

The probe team is also examining the failure of federal and Punjab governments to provide sufficient security to Benazir Bhutto during the election campaign and take action against officers guilty of negligence.