Chandigarh, April 3 -- The counter intelligence (CI) wing of Punjab Police detained two key suspects from Ropar district in connection with a blast outside the Punjab BJP headquarters in Chandigarh on Thursday. Those detained have been identified as Aman Singh, alias Bholu, and Gurtej Singh, both residents of Rattangarh village in Morinda. Officials familiar with the matter said the CI wing launched an operation immediately after getting information that the accused had reached Ropar district through Mullanpur. Both had hurled a grenade at the BJP headquarters in Sector 37 on Wednesday evening and used a motorcycle to flee, said officials. Earlier in the day, the UT police said the attack was part of a broader pattern of incidents unfolding in Punjab, with the attackers allegedly planning more such strikes. Besides National Investigation Agency (NIA), Punjab Police's Anti-Gangster Task Force AGTF and counter-intelligence units are coordinating in the probe. Terror group Babbar Khalsa International (BKI) claimed responsibility for the blast in which no one was injured. A video surfaced on social media showing a person wearing a helmet throwing a grenade while another person recorded the act. After the object was hurled, both started running, followed by the sound of a blast. Their faces were not visible in the 10-second video, the veracity of which was yet to be ascertained. In a message circulated on social media, purportedly from Sukhjinder Singh Babbar of the BKI, claimed that the blast was in response to "targeted killings" of Sikh youth and warned that those responsible for the killing of 19-year-old Ranjit Singh in Gurdaspur would not be spared. A similar incident also occurred on March 30 when a blast rocked a police station complex in Amritsar. A UT police official, privy to the development, said the perpetrators followed similar modus operandi in the Chandigarh attack, too, wherein two unidentified motorcycle-borne assailants reportedly hurled an explosive object before fleeing. Here too, a little-known outfit, Khalistan Liberation Army, claimed responsibility for the blast, referring to the 'encounter' of Gurdaspur youth. Investigators said the attack was not an isolated act but linked to a series of targeted attempts aimed at creating panic and drawing attention to the youth's death. Ranjit, 19, was one of the three persons accused of killing two police personnel at a police post in Adhian in Gurdaspur on the morning of February 22. Three days later, Ranjit was killed in a police encounter near Puranashala village, about 8 km from Gurdaspur on the Gurdaspur-Mukerian road. Police had said that the murder was carried out at the behest of Pakistan-based handlers and the ISI. However, the family of the deceased have contested police claims. "We suspect that recent grenade attacks on establishments, including the BJP office, are being used to amplify the narrative around Ranjit Singh's killing, with possible involvement of cross-border elements and radical outfits," a Chandigarh Police official mentioned, pleading anonymity....