The Shillong-bound bus left the district headquarters Tura last evening and the accident occurred at around 11 PM at Dollonggre village, about 50 km away from Tura, the district headquarters.
"At least four persons have died. Five critically injured persons were shifted to a Guwahati hospital," Inspector General of Police (Western Range) H Nongpluh told PTI.
Other injured were taken to the Tura Civil Hospital, he said.
The bus had to be cut open to retrieve the bodies and rescue the passengers.