An explosion was heard in a public park not far from the residence of Pakistani President Gen. Pervez Musharraf. There were no immediate reports of injuries, and the cause was unclear. Police and other security forces have cordoned off the Ayub Park, site of the reported blast, in the garrison city of Rawalpindi, a senior army official said on condition of anonymity because he lacked the authority to make formal media comments. Mohammed Azhar, a police control officer in Rawalpindi, said that there were no reports of injuries from the explosion and its cause was unclear. "Whatever that has happened, it was inside the park," Azhar said.