Three persons were killed and 27 others feared drowned after a bus carrying mostly 'kanwarias' fell into the Bhagirathi river in Uttarkashi district on Friday morning.
In a separate accident near Devprayag area of Tehri district, three persons were killed and 22 injured, five of them critically, when a bus fell into a gorge.
Police said the first mishap took place when the bus carrying 43 pilgrims was going to Gangotri shrine.
Three bodies have so far been fished out from the swollen river and 13 people have been injured.
Apart from the kanwarias (devotees of Lord Shiva), the bus was also carrying some teachers.
Police said the hope of finding any survivors was slim as the river was turbulent due to heavy rains in the catchment area during the past two to three days.
Chief Minister R P Nishank expressed grief over the accidents and asked the district administration to provide medical aid to the victims.
He also announced a compensation of Rs 50,000 to the next of kins of the deceased.