Punjab Police on Monday said it has foiled a Pakistan-based ISI-backed module that was allegedly planning grenade attacks on police establishments in Punjab and other states.Three people were arrested in connection with the case and police recovered two hand grenades and a Glock pistol from them.Preliminary investigation has revealed that the Inter Services Intelligence supported module was involved in systematic targeting of police establishments in several states, which has now been successfully averted.Director General of Police Gaurav Yadav said the grenade bore the POF (Pakistan Ordnance Factory) mark, indicating cross-border links, PTI reported.The arrested people have been identified as Sarabjit Singh, resident of Ammishah village, Tarn Taran, Bikramjeet Singh, resident of Nangal Pannuwan village, Amritsar, and Amandeep Singh, resident of Indra Colony, Amritsar.Sharing operational details, Assistant Inspector General, State Special Operations Cell, Amritsar, Sukhminder Singh Mann said that in the intelligence-led operation, SSOC police teams arrested Sarabjit Singh and Amandeep Singh and recovered hand grenades and a pistol from their possession.During investigation, the police found that Bikramjit Singh, the key operator and primary contact of Pakistan Intelligence Operatives (PIO) in the group, was operating from Deesa, Gujarat.The information was immediately shared with ATS Gujarat and with their active cooperation, SSOC arrested Bikramjit Singh, Mann said. He said the investigation also revealed that all the accused were in touch with the PIO through social media platforms.He said the investigation also revealed that the group, acting on the instructions of ISI handlers, was planning to carry out grenade attacks on various police establishments in Punjab and other states.Police said efforts are on to identify, trace and arrest other members of the module.An FIR has been registered at Amritsar police station State Special Operation Cell (SSOC) under the Explosive Substances (Amendment) Act, Arms Act and Indian Justice Code (BNS).