The Pir Panjal tunnel, which runs below the 2.5 km Jawahar tunnel, connects the Bichelri valley of Banihal in Jammu with Qazikund in Kashmir and is to link J&K to the Indian rail network through the year.
The army early on Thursday foiled an infiltration bid by terrorists on the Line of Control in Poonch district of Jammu region.
Security has been beefed up across Kashmir ahead of Prime Minister Narendra Modi's maiden visit to the Valley on July 4. Police and paramilitary forces have set up barricades at many places in the summer capital of the state and other major towns for carrying out searches of vehicles, the police said.