Security has been strengthened at vulnerable places and key installations across Punjab, Haryana and their joint capital Chandigarh in view of Republic Day celebrations on Tuesday.
Additional forces have been posted at bus stands, railway stations and government buildings, officials said in Chandigarh on Monday.
Both the states and Chandigarh are already on high alert following the terrorist attack at Pathankot recently.
While Punjab chief minister Parkash Singh Badal is indisposed and will not be able to unfurl the tricolour at Amritsar as scheduled earlier, his Haryana counterpart Manohar Lal Khattar will unfurl the flag in Gurgaon.
Punjab and Haryana governor and Chandigarh UT administrator Kaptan Singh Solanki will unfurl the flag at Chandigarh.
All check posts along the inter-state borders on Punjab and Haryana too have been put on maximum alert, officials said.
Services of dog and bomb squads have been utilised at vulnerable locations across Punjab and Haryana, officials said.