An explosion took place at the headquarters of the intelligence wing of the Punjab Police in Mohali Monday night at around 7.45 pm at the office located at sector 77 in Mohali when a rocket-propelled grenade hit the Intelligence Wing headquarters of Punjab Police, shattering windowpanes on one of the floors of the building. Following the incident, which raised a security alarm in the state and political outcry, three people have been held in connection with the case.