Afghanistan's intelligence agency said Saturday it has handed over evidence to Pakistan that the assassination of former Afghan president Burhanuddin Rabbani was planned in Pakistan.

Afghanistan's National Directorate of Security, or NDS, said the September suicide bombing that killed Mr. Rabbani was plotted in Satellite, a suburb of the Pakistani city of Quetta.

Taliban leaders are believed to be based in Quetta. Their leadership council is known as the Quetta Shura. The Taliban has not claimed responsibility for Mr. Rabbani's killing.

An NDS spokesman said the agency has arrested key people involved in Mr. Rabbani's murder plot. He said the detainees have provided details about the assassination, linking the suicide bombing to the Taliban leadership.

The NDS spokesman said the evidence and documents have been submitted to the Pakistani embassy in Kabul. He said additional details would soon be released by a commission set up to investigate Mr. Rabbani's death.

Mr. Rabbani, who headed up efforts to broker peace with insurgents, was killed at his Kabul home by a suicide bomber claiming to be carrying a message of peace from the Taliban leadership.