The union home ministry has alerted the north-eastern states over possible terror attacks in the run-up to Independence Day, officials said Sunday.
The ministry has asked the states to take steps to foil any attempt by militants to upset peace.
"The home ministry has alerted the north-eastern states to maintain strict vigil in the run-up to the Independence Day and thwart any attempt by separatist outfits to create a violent situation," a Tripura government official said.
"The central and state governments have also asked the Border Security Force (BSF) to further tighten vigilance along the India-Bangladesh border to prevent trans-border movement of militants," he said.
The BSF, Central Reserve Police Force (CRPF) and other central paramilitary personnel, accompanied by bomb disposal and dog squads, are continuing search operations at airports, hotels, bus and railways terminals, markets, congested locations and national highways.
Four north-eastern states -- Tripura, Meghalaya, Mizoram and Assam -- share a 1,880-km border with Bangladesh, while India and Bhutan share a 643-km unfenced border.
Four states of the region - Mizoram, Manipur, Nagaland and Arunachal Pradesh - also share a 1,640-km unfenced border with Myanmar.
Arunachal Pradesh also shares a 1,080-km unfenced border with China.
Several separatist outfits, including the United Liberation Front of Asom (ULFA), have called for a 17-hour general strike from Aug 14 midnight and for boycotting the Independence Day celebrations. They have mailed statements to media organisations in this regard.
"We are yet to get any confirmation that the militant outfits have called a strike and boycott of the Independence Day celebrations," Tripura Inspector General of Police (Police Control) Nepal Das told IANS.
He said police have received a tip-off that extremists were trying to create a violent situation in Gandachara in northern Tripura. Police officials have reached the area and launched a combing operation to nab the rebels.
The Northeast Frontier Railway has also taken up security measures regarding the running of trains in Assam and Tripura.
An official of the Airports Authority of India said in Guwahati that entry of people, except passengers, into airport areas across the northeast has been barred and the restrictions would continue till Aug 20.
