At least seven security personnel were killed and 15 others injured when a bomb hit a convoy of a senior judge in Pakistan\'s southern port city of Karachi on Wednesday morning, said local officials. Sharjeel Memon, Information Minister of Sindh Province, said that the blast took place at Burns Road in central Karachi while Justice Maqbool Baqar Hussain and his convoy was on the way to Sindh High Court. The bomb, which contained an estimated six to eight kg of explosives, was planted on a motorbike parked by the roadside and it was triggered off through a remote control device while Baqar\'s convoy was passing by. Six policemen and a Ranger man were killed in the blast and 15 others including seven to eight security personnel injured. The blast also destroyed one police mobile and a Rangers motorbike as well as some other nearby buildings. The injured people were shifted to Civil Hospital where at least seven of them were said to be in critical condition, said Medical Superintendent of the hospital. Deputy Inspector General Ameer Sheikh said Justice Baqar has been shifted to Agha Khan Hospital and his condition is critical. No group claimed responsibility for the attack yet. Both President Asif Ali Zardari and Prime Minister Nawaz Sharif condemned the blast and directed hospital administration to provide best medical treatment to the injured people.