The 24-year-old man was found dead inside an under-construction building in Guwahati’s Bhetapara area on Saturday.
The deceased, identified as Mithun Das, was found with his legs and hands tied, sources said, adding that he was a resident of Nagarbera of Kamrup district.
Following the discovery, city police reached the spot and recovered the body.
Meanwhile, a case of murder was registered by his family members at Basistha police station.
He used to work as a helper at a nearby building for the past seven years, his family said.
They further claimed that Mithun could never have committed suicide as he was not mentally depressed to take such an extreme step and urged authorities to launch an investigation into the matter.
Acting swiftly, the police detained seven persons in connection to the incident and initiated interrogation.