Siliguri, 14th August: Ahead of the 76th Independence Day on Tuesday, security has been tightened in Siliguri. In view of the national day, police are engaged in patrolling the populated areas of the city including Bidhan Market, shopping malls of the city and railway stations. As per reports, on Monday, Siliguri Police conducted a search of the busy and crowded Bidhan market area with the help of dog squad.