A special team of the National Investigation Agency on Sunday inspected the scene of the twin blasts here, officials said.
Back-to-back blasts in Narwal on the outskirts of Jammu City had left nine people injured on Saturday.
Police suspect that improvised explosive devices were used to carry out the twin explosions in an SUV parked in a repair shop and in a vehicle at a nearby junkyard at the Transport Nagar area.
The explosions occurred at a time when security agencies in the region are on high alert for the Congress' ongoing Bharat Jodo Yatra and the upcoming Republic Day celebrations.
The National Investigation Agency team visited the site of the blasts in the morning and the federal anti-terror agency is likely to take over the case for a thorough probe, the officials said.
Officers of the probe agency spent over an hour at the scene of the blasts and collected samples before leaving. Senior officers of the Indian Army also visited the area for inspection for the second day, the officials added.
The area is still under a security cordon and a massive sanitisation operation is underway, they said.
(PTI)