A 22-hour standoff between the army and two to three ultras holed up in the BSNL exchange building in Indira Nagar in Badami Bagh area in Srinagar was showing no signs of ending on Wednesday afternoon, even as security forces fired rockets and mortar shells at the building.

The militants entered the building after killing a Central Reserve Police Force head constable and three other jawans at 1815 IST on Tuesday, official sources said.

Earlier report: Efforts on to flush out Srinagar militants

Although the building has caught fire and an adjacent house is also gutted, the militants, now occupying the ground floor, are continuing to fire at the security forces.

All telephone connections from the Indira Nagar exchange, including those at the nearby headquarters of army's 15 corps, have gone dead.
 
Over 15 persons, including seven special security bureau personnel and three BSNL employees have been evacuated from the building.

Two army personnel, including a captain, were injured during an exchange of fire initiated by security forces to provide cover to the trapped SSB personnel, official sources said.

Security agencies believe that Al-mansoorian, a shadow outfit of Lashkar-e-Tayiba, is behind the attack.