Mumbai, Mar 24 (IANS): In a major development in the investigation into the SUV case, the National Investigation Agency (NIA) has slapped charges under the stringent Unlawful Activities (Prevention) Act against arrested-suspended Mumbai Police 'encounter specialist' Sachin Vaze, officials said on Wednesday.

An NIA official related to probe told IANS: "The agency has added the sections of the UA(P)A against Vaze, who was arrested on March 13 in connection with Scorpio SUV with 20 gelatin sticks and a threat note, parked near Antilia, the home of industrialist Mukesh Ambani."

Billed as a prime accused, Assistant Police Inspector (API) Vaze was arrested for his role in the case and sent to NIA custody till March 25.

The NIA had taken over the SUV case probe on March 3 after notification from the Central government.

The Maharashtra Anti Terrorism Squad (ATS), which is probing the businessman Mansukh Hiran's death aspect of the case, was planning to seek Vaze's custody on Thursday.

Earlier this week, the ATS had announced that it had cracked the Hiran case with the arrest of two persons and was in the process of winding up the probe.

However, late last week, the MHA asked the NIA to also take over probe the mysterious death of Thane-based businessman Hiran, whose body was found from the marshes in Thane Creek on March 5.

At a hearing this afternoon, a Thane court has directed the Maharashtra ATS to hand over to NIA all the case papers pertaining to the Hiran death case, as per the Centre's directives.