One infiltration bid was foiled in Naugam sector, another in Tangdhar sector and the third one in Gurez sector.
"Alert soldiers posted along the Line of Control in Naugam sector noticed some suspicious movement and challenged the intruders," an army official said.
The militants opened fire at positions of security forces which was "effectively retaliated", triggering a gunbattle, he said.
Four militants were killed and war-like stores were recovered from the scene of the gunbattle, the official said. The operation is still in progress.