KARACHI, March 10: A 12-member team of US Federal Bureau of Investigation agents left the city for home on Thursday night after completing a week-long forensic investigation and collecting samples for further tests. The tests would be carried out in the United States, officials said.

The FBI agents had arrived here from the United States on March 4 to join in their associates, who had rushed Karachi from Islamabad and Kabul following the March 2 suicide bombing near the US consulate in the city.

The bombing left five people, including a US official, dead.

The scene of the blast has been cleared of the wreckage by now, although the crater that had developed due to the blast has blocked the entrance to the consulate. As an alternative access, a new approach has been opened from the service road parallel to the Abdullah Haroon Road, according to a senior police officer.

The FBI team’s activities were described as a part of the joint investigation by the FBI and local agencies. A police official said that the joint probe it remained restricted to selective sharing of information.

So far, the week-long investigation has even failed to establish the identity of the suicide bomber despite the man having been caught on the surveillance camera of the consulate.

“Security for the consulate has been beefed up further as more personnel of the law-enforcement agencies have been deployed around the mission,” the police official said.

Officials said that an Al Qaeda-linked group, opposed to President Pervez Musharraf, had come under suspicion for its involvement in the March 2 attack outside the US consulate in Karachi on the eve of President George W. Bush’s visit to Pakistan.

However, some investigators were of the opinion that a previously unknown group might be behind the bombing.

Police believe that a suicide bomber, aged between 20 and 25 years, used the explosive-laden white car to ram a US diplomat vehicle, killing the diplomat, his Pakistani driver and a security official.

The US State Department identified the diplomat as David Foy, a facilities maintenance officer and father of four daughters. His daughters had been to Pakistan last year.

The deceased driver was identified as Iftikhar Ahmed. A Ranger official on duty at the scene of the incident also died in the blast.

Later, one of those injured in the blast, Hasan Shahzad, 18, who was a security guard employed by the SMS, succumbed to his wounds at the PN Shifa Hospital, pushing up the death toll to five.

The explosion ripped through the car parking area of the Marriott Hotel, destroying 23 cars and damaging several others, including seven of the US mission.