After the collision, another car rammed into the vehicle from behind, leaving four of its occupants injured, police said.
A 28-year-old woman and a 25-year-old man, both nationals of the Netherlands, and their driver were killed on their way to Bikaner, they said.
The injured were being treated at PBM government hospital, they said.
An FIR has been registered against the driver of the state roadways bus, they said.
