He said initial inputs of the encounter, in which five security personnel and a civilian have been killed till now, suggest that the modus operandi adopted by the militants bore similarity to attacks that had occurred in Udhampur in J-K and Gurdaspur in Punjab recently where security personnel were targeted.
"Lashkar (LeT) appears to be behind this...the operation is still on. It is suspected that there could be 3-5 militants who are involved in the attack. The assault by security forces is in its final stages," Mishra told journalists here.
He said it is understood that the militants are heavily armed with weapons like AK-47 assault rifles and grenades and "certainly" came prepared for a long operation given the huge cache of arms and ammunition they hold.
Mishra, who had recently toured the Kashmir valley, said the area where the attack took place is a "volatile" zone as sometime back also militants had attacked a Central Reserve Police Force (CRPF) squad around here.
The paramilitary force chief said security forces are "always" on alert while making their movement in these areas as he refused to go into the specifics of any intelligence input being received in this regard.
Officials said while an Assistant Commandant-rank officer of CRPF Rakesh Raman was critically injured and admitted to a hospital ICU, area commander of the force and Inspector General (Kashmir zone) Atul Karwal and an another trooper have received minor injuries while tackling the militants holed up in the EDI building.
The assault inside the building was later taken over by the army which has lost two Captain-rank officers and a Lance Naik from the elite PARA (Special Forces) unit.
Two CRPF men were killed on Saturday when militants attacked a 300-personnel strong bus convoy of the force while they were traveling from Jammu to Srinagar. Nine CRPF personnel on the bus were injured during the attack.
Mishra said it is suspected that the militants came to attack the convoy of the force and may not have a plan to take hostages in the EDI building.
The CRPF DG said the escort party of the convoy that came under attack mounted an effective retaliation and hence the militants fled and hid in the Entrepreneurship Development Institute (EDI) building.