Kolkata: Four friends of a man in his 30s, whose body was found next to a footpath near Gariahat with no apparent external injuries on March 26, were arrested two days ago after a post-mortem report on May 15 found ante-mortem injuries and broken ribs as the reasons behind his death.A case of murder was lodged soon after the autopsy report arrived. Probe revealed that the deceased, Vinod Das, a computer service professional and father of two, borrowed Rs 14,000 from one of the friends, Nilanjan Goswami (alias Babla), of which he returned Rs 5,000 but couldn't return the rest. Over this, Goswami apparently kidnapped Das and assaulted him till he died. The friends apparently dumped him on the sidewalks of Purnadas Road near Gariahat and fled.Locals informed police, who took him to a hospital where a doctor declared him dead. Initially believed to be a case of excessive alcohol consumption, the post-mortem later revealed a far more chilling truth — four broken chest bones, a fractured skull, and signs of blunt force trauma, indicating a fatal beating."We realised it was a murder in disguise. The victim's father named two suspects, Subhadip Law and Nilanjan Goswami. Shockingly, Goswami posed as a sympathiser during the initial probe," Kolkata Police posted on Facebook.Following a complaint by Das's father, Gariahat police launched a murder probe. Within two days, four suspects were arrested — Law, a transport businessman, Goswami, an IT professional, and two local acquaintances, Arvind Kumar Sahu and Joginder Chaudhary.Police revealed that Goswami once taught English to Vinod to help him get a job. All four are in police custody.