The Afghanistan capital of Kabul was shaken by a large explosion Saturday afternoon that was followed by gun shots, witnesses say. There were no immediate reports of casualties, Khaama Press reported. The blast occurred near Burhanuddin Rabbani university near a camp where afghan tribal leaders are scheduled to meet next week to discuss a bilateral security agreement with the United States. The agreement would establish the status of 10,000 U.S. troops scheduled to stay in Afghanistan after most Western forces withdraw by the end of 2014, the BBC reported. The agreement must be approved by the Afghan parliament and the Loya Jirga council.