The incident took place when a vehicle without a registration plate was signalled to stop during Naka checking at Pulwama chowk in Sopore, 45 kms from here.
However, the driver of the vehicle, which was carrying the militants, ignored the signal and they sped away.
Head Constable Ghulam Mohammad was injured when the militants opened fire after being chased by a police team.
He has been admitted to a hospital here in critical condition, they said, adding that security forces have been put on alert in Baramulla and adjoining areas to nab them.
