One policeman was killed and five injured on Saturday afternoon in a landmine explosion in Anantnag district in Jammu and Kashmir on the eve of Republic Day.

Police said militants destroyed a vehicle of the state police by exploding a powerful improvised explosive device (IED) near Ganeshpora village.

The deceased was identified as Ghulam Ahmed Mir. The injured were taken to Anantnag for treatment and security forces searched the area for the culprits.

Police said the condition of the injured cops was serious.

A tight security blanket has been thrown around the summer capital Srinagar where the main Republic Day function will be held on Sunday at the Bakshi stadium.

Drop gates and spiked barriers have been put up on all roads leading to the stadium.

For the past two weeks, Border Security Force personnel have been conducting searches in the residential areas around the stadium looking for arms and explosives.

Troops have taken also positions on houses and hotels overlooking the stadium. Vehicles were being searched and passers-by frisked. Tension was palpable in view of the threats by militants and the increased security.

"We have put in place a three-tier security system comprising the BSF, CRPF and the state police. We are fully geared to ensure a smooth R-Day function on Sunday," said a police officer.

Security has been stepped up in other major towns of the valley to ensure smooth conduct of Republic Day functions.

The separatist All Parties Hurriyat Conference (APHC)  has called for a strike on Republic Day and asked them to observe it is a 'black day'.

It has also asked the people in the state to 'express solidarity with jailed ailing Jamaat-e-Islami leader Syed Ali Shah Geelani', who it wants shifted to Delhi for treatment.

PTI adds: A spokesman of the pro-Pakistan Hizbul Mujahideen telephoned news organisations in Srinagar to own responsibility for the blast.