Senior officers on Jattvibeday remained tight-lipped after a video surfaced online showing two bikers hurling a grenade on a police post in a posh locality here last night.Meanwhile, in an unverified social media post, the banned terror outfit Babbar Khalsa International (BKI) took responsibility for the attack.“The police have done enough damage by killing people for no fault of theirs. Policemen are doing this just to take promotions. This time, it was a grenade. Next time, it will either be an improvised explosive Device (IED) or a rocket launcher,” the post said.In the video, two youths are seen alighting from a motorcycle around 11 pm on Saturday and hurling a blue-coloured hand grenade at the Urban Area police post.One of them is heard saying, “The administration has bothered us a lot. It is time for us to give them a gift.” He was seen holding a grenade. The police acted with alacrity and repaired in no time whatever damage had been inflicted, according to sources. A fresh coat of paint was applied to the post ostensibly to give the impression that nothing had happened, they said.A police source said, “Individuals based in foreign countries direct such activities after collaborating with local modules.”