Three employees of the Institute of Science and Bio Resource (ISBR) were found dead inside the institute at Umsawli, New Shillong Township last night.
The bodies of Sheba Kharbani (40) and Rupert Donbor Dohtdong (43), both working as cleaners and Backstar Kharkrang (30), a chokidar were found in a portion of the under-construction institute. All are residents of Mawlai Phudmuri.
Police opened one of the rooms of the institute after receiving complaints of foul smell emanating from inside.
Authorities are yet to confirm the cause of death, but suspects that they could have died from mushroom poisoning.
The crime scene unit along with the forensic team examined the spot. The bodies were later shifted to NEIGRIHMS for post-mortem.
Police have registered a case of unnatural death.