Chandigarh, June 16 -- An illegal Bangladeshi migrant has been arrested for making hoax bomb threats targeting city schools and the Punjab Civil Secretariat in January this year, police said on Monday. The accused, Saurav Biswas (30), is the first person to be arrested in connection with the recent string of such incidents. Majority of the cases are still unsolved. Emails citing a bomb threat were sent via email to Tender Heart School in Sector 33, Government Model Senior Secondary School (GMSSS), Sector 16, GMSSS, Sector 35, and GMSSS, Sector 19, on January 28. The Sector 17 police station had registered the case under Sections 113(3) (terrorist acts), 62 (attempt to commit offences) and 351(4) (criminal intimidation) of the Bharatiya Nyaya Sanhita (BNS) and Section 66(F) of the Information Technology (IT) Act. On January 29, another such email was sent to the Punjab Civil Secretariat, triggering registration of another FIR at the Sector 3 police station under Sections 351(4) of the BNS and 66(F) of the IT Act. Investigation based on technical analysis of the emails in both cases led to the accused, Saurav Biswas, a resident of West Bengal who had earlier crossed over from Bangladesh illegally, police said. The accused was initially arrested by the Cyber Crime police station in Ahmedabad, Gujarat, for a similar hoax threat. The Chandigarh Police subsequently obtained his production warrant, arrested him on June 2 and obtained remand to further investigate the case. The police said that the accused is a tech-savvy freelancer who provides web design and animation services online. He was involved in buying and selling Gmail accounts through various Facebook pages. He had procured around 300 Gmail accounts online, out of which 219 were sold to a Bangladesh-based individual. In addition to the cases in Chandigarh, he has been involved in several other incidents, with FIRs registered against him in Delhi's civil lines police station, special cell and Dwarka cyber police station, officials added....