Updated on Thursday, July 02, 2009, 17:11 IST

Islamabad, July 02: At least six people were killed and over 25 injured on Thursday when a motorcycle-borne suicide bomber struck a bus carrying employees of a top nuclear facility in the Pakistani garrison city of Rawalpindi near here.

The bomber rammed his motorcycle into the fuel tank of the bus at Chuhr Chowk, a busy commercial area located near the cantonment in Rawalpindi, a little after 4 pm local time, Regional Police Officer Nasir Khan Durrani told reporters.

At least six persons were killed and over 25 people, including passersby and people in other cars, were injured in the blast, officials said.

The body parts of the bomber and components of the motorcycle were gathered by investigators soon after the attack.

The bus belonged to the Pakistan Atomic Energy Commission and was carrying about 50 to 60 government employees, Rawalpindi police chief Rao Muhammad Iqbal told Dawn News channel. It was followed by other vehicles from the same department, he said.

Media reports said the bus was carrying employees of Khan Research Laboratories, one of Pakistan's top strategic atomic facilities named after nuclear scientist A Q Khan. However, there was no official word on this issue.

The injured were taken to several hospitals, where an emergency was declared by authorities. The blast also damaged about two dozen vehicles.

No group claimed responsibility for the attack. However, Pakistani Taliban commanders had recently vowed to carry out attacks across the country in retaliation for the military operations being conducted against militants in the north-western Swat valley and other troubled areas.

Security was further tightened in Rawalpindi and Islamabad following the attack.

Both cities were placed under an extensive security blanket some weeks ago in the wake of a wave of bombings and suicide attacks across Pakistan.

Bureau Report