The 'Sada-e-Sarhad' bus, which runs between India and Pakistan, met with an accident near Jahankhela village in Fatehgarh Sahib on the GT Road on Tuesday, police said.
Police said due to rain the road was wet and when the driver applied breaks the bus skidded, hitting the escort vehicle.
The policemen, who were sitting in the escort vehicle, received minor injuries. They were discharged after being administered first aid at the civil hospital in Rajpura, they said.
The bus, which runs between Delhi and Lahore, later resumed its journey, police said.