Mumbai, Oct. 4 (PTI): Fugitive underworld don Dawood Ibrahim and brother Anees Ibrahim have been named suspects in a Rs 3-crore extortion case involving a builder in which their sibling Iqbal Kaskar is already booked, police said today.

This is the first such case in which Dawood, the prime accused in the 1993 Bombay blasts case, and his brothers have been named, said an official of the Thane crime branch that is handling the case.

The crime branch had yesterday registered the extortion case on the complaint of the builder against Kaskar and some gang members of Dawood, the officer said. During investigations, the alleged role of Dawood and Anees came to light and the two were listed as wanted accused, the officer said.

Anees allegedly threatened the builder - himself arrested some months ago over a land ceiling scam - to drop his claim on a plot as Anees had helped another realtor in the deal, the officer said. Some men close to the other realtor had gone to meet a close aide of Dawood in Dubai, allegedly to put pressure on the builder, the officer said. "We have asked for the passport details and we will investigate their route," the officer added.

Kaskar and two of his aides were arrested last month in another extortion case.