A low-intensity explosion was reported outside the Punjab BJP headquarters in Chandigarh on Wednesday evening, triggering security concerns and prompting security agencies, including the National Investigation Agency (NIA), to launch an investigation. No casualties were reported in the incident. The banned outfit Babbar Khalsa International (BKI) has claimed responsibility for the attack.Senior Superintendent of Police Kanwardeep Kaur said prima facie, it appeared a small crude-type device was thrown towards the building. BJP leader Vineet Joshi, who was inside the building with other party leaders, said they heard a blast at around 5 pm in the parking area.According to eyewitnesses, the device was intended to be hurled inside the premises but was misdirected, landing instead on a stack of sand nearby. An Activa, reportedly parked at the location since morning, along with a Sedan car, sustained damage in the explosion.Police teams reached the spot within a few minutes of the blast. The area was immediately cordoned off and BSF personnel were deployed to secure the BJP office. A Central Forensic Science Laboratory (team was later called in to collect evidence. A NIA team was at the site to investigate the blast. A bomb detection squad also joined in to sanitise the area.Meanwhile, BKI claimed responsibility for the attack. In a message released in Punjabi, one Sukhjinder Singh Babbar said violence against Punjab’s youth would be met with retaliation. The blast is claimed to be in retaliation of the encounter of Ranjit Singh in Gurdaspur.Ranjit Singh, 19, a Gurdaspur resident, was among the three youths accused in the double murder of an ASI and a Home Guard near the Pakistan border on February 22. He was allegedly killed in an encounter on February 25.According to the Chandigarh Police, a viral video by the same group showing a person pulling the lever of a grenade appears to be authentic, though further clarity would emerge after a detailed investigation. The police have registered a case against the unknown person(s) and launched an investigation.