The incident took place last Friday night at around 9 pm at Umpleng Cement area located along the Saipung-Khliehriat border in the district, they said.
The mishap took place after the cables pulling up the trolley containing coal snapped sending it plummeting down. After that the trolley landed on top of the five labourers crushing them to death.
The bodies of all those who died were extracted and post-mortem examination has also been completed.
All the labourers hail from Nayadanga village in Assam's Karbi Anglong district. Arrangements are being made to send the bodies of the deceased to their native village after completion of all formalities, police said.
They were identified as P Taru (50), Shankar Keoq (20), Sanjoy Sahu (36), Robrap Keoq (38) and Ronu Teshu (36).