NEW DELHI: In what would eliminate doubt over Pakistan's involvement in the Pulwama attack in which 40 CRPF men were killed last Thursday, forensic experts have concluded that the suicide bomber had used high intensity 'military grade' explosives (RDX) which terrorists procure from Pakistani defence forces.The forensic experts have also concluded that the explosive-laden vehicle used by the Jaish-e-Muhammed terrorist was a Maruti Eeco van.In their report on preliminary findings after visiting the spot of Thursday's ghastly attack, experts said although RDX is a "very stable" explosive and the one used in the car bomb may have been brought to India months back, it was "definitely assembled" in India and that too "within a range of 5-7 km of the blast site".Although rain washed away some vital evidence after the attack and a final forensic report is awaited, a senior expert claimed the RDX used in the blast could be 50-70 kg as explosives in the range of 100-300 kg would have caused "more damage"."The final report would take some time, but it appears that more than one highly trained bombmaker travelled to India to assemble it and the trigger switch, detonator and power fuse might have been attached to it closer to the time of attack," the expert told TOI, requesting anonymity.Intelligence sources said every gram of RDX available with the Indian Army is audited but the Pakistani military is known for supplying explosives to terror groups.The expert, who specialised in study of IEDs and explosives used in bombings world over, has also opined that this is the "first ever such bombing" in India mirroring vehicle-borne suicide bombings carried out by Islamic State and al-Qaida terror groups in West Asian countries. There was a massive black smoke after the blast, and everything melted, like seen in car bombings in West Asia.He also ruled out the Pulwama bomb being completely similar to the 2000 Badami Bagh suicide car bomb and the one used in the 2001 J&K assembly attack in which a terrorist rammed a car into the gates of the assembly before blowing it up. "While the teenager in the Badami Bagh incident had panicked before the attack, the J&K assembly bomber also took some time to trigger the bomb," he said.This shows that Pulwama bomber Aadil Ahmad Dar was fully prepared mentally to blow himself up along with the CRPF jawans, a theory which gives little credence to the possibility of somebody else triggering the bomb from a distance. Intelligence and investigation agencies are worried that military grade explosives such as RDX, PETN (Pentaerythritol Tetranitrate), TNT (Trinitrotoluene) are being used by terrorists in Kashmir.