"We will not forgive Pakistan's actions. It will prove to be Pakistan's foolishness and will cost them dearly," Ahir said.
Army Vice Chief Sarath Chand said that India will continue to give a "befitting reply" and its action will speak for itself.
The Pakistani Army has been supporting infiltration by terrorists along the border, said.
"We will continue with our process of giving a befitting reply," he told reporters.
"(Our) action will speak for itself," Chand added in response to a question on Sunday's incident.
On Sunday night, Pakistan initiated unprovoked firing along the LOC in Rajouri district that claimed the lives of four soldiers -- one officer, three jawans -- while another two were injured. In January, schools along the International Border and the LoC in five districts -- Jammu, Samba, Kathua, Rajouri and Poonch -- were closed for over a fortnight because of firing and shelling by Pakistani troops.
All schools situated within five kilometres of the Line of Control in Rajouri district in Jammu and Kashmir have been closed by authorities for three days in view of firing and shelling by Pakistani troops, an official said today.
With inputs from PTI
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