The entire security grid in and around Jammu and in other districts of Jammu Division has been put on high alert to thwart possible strike by militants on the eve of Republic day celebrations. Ahead of the Republic day, Jammu and Kashmir Chief Minister Omar Abdullah reviewed the overall security situation in the State with top officials of the Army, Police and Civil Administration in Unified Command Meeting yesterday. The meeting came at a time when militant activities have increased in the state with Pakistan making repeated attempts to infiltrate militants into Jammu and Kashmir to disrupt Republic day celebrations. <br/>Security forces achieved a major success late yesterday when they gunned down a top Hizb-ul-Mujahideen operative in a fierce encounter in Kishtwar district and recovered one AK rifle, one pistol, grenades and a radio set. Police also averted a major tragedy with the timely recovery of a huge quantity of arms and ammunition from a terrorist hideout during a search operation in Lancha Bakhi Walla area of Mahore in Reasi district. Our correspondent quoting official sources reports that arms and ammunition was dumped by the militants possibly to be used to disrupt Republic Day celebrations.