LUCKNOW, India (AP) — A double-decker passenger bus collided with a milk truck in northern India on Wednesday, killing at least 18 people and injuring many others, officials said.

The collision occurred on an expressway in Uttar Pradesh state, and 19 injured people were rushed to the hospital by villagers in the area, said police officer Arvind Kumar, adding that their condition was reported to be stable. The bus was traveling from the northern state of Bihar to the capital New Delhi.

"Authorities are in the process of identifying the victims, and a probe has been launched to determine the exact cause of the accident,” Kumar added.

Gaurang Rathi, a government official, said that according to a preliminary investigation the bus may have been speeding when it struck the milk truck from behind, which led both vehicles to overturn. The collision was severe enough that one side of the bus was torn off, causing passengers to be ejected from the vehicle. Images on television showed bodies scattered across the road.

India has some of the highest road death rates in the world, with hundreds of thousands of people killed and injured annually. Most crashes are blamed on reckless driving, poorly maintained roads and aging vehicles.

In May, a bus carrying Hindu pilgrims skidded and rolled into a deep gorge on a mountainous highway in Indian-controlled Kashmir, killing at least 21 people.