Delhi police have arrested a 47-year-old scientist of DRDO for a bomb blast at Rohini district court.

Identified as Bharat Bhushan Kataria, he wanted to kill advocate Amit Vashisht, who is his immediate neighbor in his colony.

Delhi Police Commissioner Rakesh Asthana said they had recovered a robe of the kind worn by advocates, as well as other “incriminating” evidence from Bharat Bhushan Kataria, who has been with the DRDO for 20 years.

Police said Kataria and Amit Vashisht lived in the same building in Ashok Vihar till three years ago and had a running dispute overuse of the common terrace. Initial investigation has shown that Vashisht had filed a criminal complaint against Kataria and, the day the blast happened, the court was to hear framing of charges which, Kataria feared, would destroy his career.

Married with two children, Kataria was also the DRDO’s liaison officer with other agencies, officials said.

 “He and Vashisht have a long-standing dispute, going back over 10 years, and have filed over a dozen civil and criminal cases against each other,” DCP (Special Cell) Rajiv Ranjan Singh said.

On the day of the blast, he added, “Kataria placed a bag containing an IED behind Vashisht and triggered the IED from a safe distance with a remote”.

The low-intensity blast caused minor injuries to a Delhi Police Constable but not any fatalities or much damage. Forensic experts and the National Security Guard (NSG) found that the circuit of the bomb kept in a tiffin had not been assembled properly, due to which only the detonator went off and not the half kilogram ammonium nitrate-based explosives.

Singh said the findings also indicated that the attacker had used easily available materials to fabricate the IED. “Components of the IED were identified from the debris, and the bag in which the IED was placed was tracked to a medical equipment multinational company. Its distributors were examined,” the DCP said.

Asthana said they recovered from Kataria’s house “several file covers, identical to those which were present in the IED bag, similar screws that were used as shrapnel in the IED, and remnants of a black adhesive tape used in fabricating the IED”.

A team led by ACP Ved Prakash scanned more than a hundred CCTV cameras and checked around a thousand vehicles that entered the court complex the day of the blast. 

“Kataria’name cropped up as a person of interest, and we found that his case was listed for hearing on the day of the blast. His opposite party, Amit Vashisht, was sitting in the row next to which the IED exploded,” Singh said.

CCTV footage showed Kataria entering the court complex at 9.33 am on December 9 wearing a black coat and trousers, resembling an advocate’s. 

“He was carrying a bag in his hand and a laptop bag on his back. He was seen entering the court from Gate No. 7 and concealing the bags outside a food outlet inside the court premises and leaving within some minutes from the same gate. After five minutes, he entered from Gate No. 8 and picked the two bags from outside the outlet. He was seen in various cameras inside the main court building and he left at around 10.35 am from Gate No. 8 with the laptop bag on his back, but without the other bag,” Singh said.

 The DCP said Kataria carried out the attack as he was “highly frustrated due to the protracted legal battle” with Vashisht. “It was causing problems in his career as well as prolonged mental harassment and monetary loss to him and his family.”