New Delhi:  The CBI on Friday announced a cash reward of Rs five lakh for providing information about the murder of RTI activist Shehla Masood, who was shot dead outside her house in Bhopal last month.

On September 3, a case was registered against unnamed persons by the Bhopal unit of the agency, CBI sources said here.

Shehla was shot dead when she was going towards her car outside her residence in posh Koh-e-Fiza locality in Bhopal on August 16.

Madhya Pradesh Police could not figure out the motive but suspected she was eliminated by some powerful persons against whom she had filed RTI applications.

Shehla had earlier gone on a hunger strike in Bhopal in support of Anna Hazare's cause. She was also involved in other causes, including wildlife conservation.

Her father Sultan Masood had said he expected no justice, being a "lower middle-class person", and did not think that police were probing the case sincerely.

He had alleged that in January, Shehla had filed a complaint with the Lokayukta that she feared threat to her life from senior IPS officer Pawan Shrivastava.