At least 13 people were killed and more than 40 injured when a bus plunged into a gorge in India's northern mountainous state of Himachal Pradesh, dpa cited police as saying Tuesday. The accident took place when the group was returning from Renuka Lake in Sirmaur district late Monday night. "The bus skidded off the road and rolled down a 60-metre gorge. All 13 dead were tourists from the nearby states of Haryana and Uttar Pradesh," local police officer Sandeep Negi said. Four passengers were critically injured and the death toll could rise, he added. A rescue operation was under way on Tuesday, with cranes lifting the bus from the gorge.