The Thane Crime Branch on 28 September arrested Pankaj Gangwar, a business man in connection with Iqbal Kaskar extortion case.
Yesterday, the Thane court had sent Kaskar and his two other aides Israr Z Saiyyad and Mumtaz A Shaikh to four-day police custody in the same case.
Earlier in 26 September, the Enforcement Directorate (ED) began investigation against Kaskar and others in regards to the same matter.
Also on September 19, the Thane Court had sent Kaskar and two others to police custody for eight days.
Kaskar was arrested on 18 September on the charges of extortion. The police said that they were investigating whether underworld don Dawood Ibrahim was involved personally in his brother's extortion rackets or not.
Kaskar used to issue threats in the name of his brother, Dawood Ibrahim.
Kaskar was nabbed against a complaint given by a builder who was facing extortion threats since 2013.