Bangladesh-based Islamic organisation Hizb ut-Tahrir (HuT) may launch a series of terror attacks across India ahead of Republic Day, the Intelligence Bureau (IB) has warned, according to reports.

IB detectives reportedly intercepted phone calls on 15 January from a Bangladeshi mobile number. The IB recorded the phrase "doctor medicine lekar jayega" while intercepting the calls twice on Friday, The Times of India reported.

The intelligence agency has alerted all state police chiefs against possible "bomb and suicide attacks" at 24 locations across India between 16 and 23 January, with HuT believed to be behind them, said reports.

"We have received a specific alert from intelligence sources that there could be a terror attack from 16-23 January. It is a countrywide alert, following which we have strengthened security measures in Ambala and Panchkula. The police will remain extra vigilant. Citizens should also cooperate with them and report any suspicious activity to the police," The Indian Express quoted Ambala-Panchkula Commissioner of Police OP Singh as saying.

HuT reportedly has the backing of Indian Mujahideen, Lashkar-e-Toiba and Jaish-e-Mohammad — the militant organisation suspected to be behind Pathankot airbase attack, in which seven Indian security personnel were killed.

"In view of this, the field staff must be sensitised to take all necessary preventive and precautionary measures, including review and strengthening of security of Army, Air Force, BSF and other vital installations," the TOI quoted the alert as saying. The alert also warned that HuT is likely to target malls, markets and educational institutions.

In the wake of terror threats, Punjab has beefed up security as it has been targeted in the past. Before Pathankot, Gurdaspur came under militant attack on 27 July. Three gunmen dressed in Army uniform first attacked a passenger bus and then the Dina Nagar police station in the Gurdaspur district, killing eight people, including civilians. All the gunmen were killed in 12-hour-long standoff.

Security tightened in Chandigarh ahead of French President's visit

Prime Minister Narendra Modi will welcome French President Francois Hollande, the chief guest of India's 67th Republic Day, at Taj Chandigarh. Security has been tightened in and around the hotel.

Union Territory General of Police RK Upadhyay and Deputy Inspector General of Police AS Cheema inspected the security arrangements at the hotel. The UT Police has put the hotel staff under scanner for Hollande's visit.

The Railway Protection Force (RPF), along with the Government Railway Police, have deployed their personnel at Chandigarh Railway Station in view of Republic Day celebrations. "We have taken several measures to enhance the security at the station. We have received directions from the authorities to increase security," the IE quoted inspector Gurjasbir Singh as saying.