Government prosecutors have accused Pervez Musharraf of being involved in Benazir Bhutto's murder and not providing enough security to the former Pakistan prime minister.
He has denied the allegations.
Police officer Mohammed Ishaq said killed prosecutor Chaudhry Zulfikar was also involved in a case related to the 2008 terrorist attack on the Indian city of Mumbai that killed 166 people.
The attack was blamed on a Pakistan-based militant group.
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