People gather after a private bus overturned and plunged onto a lower road, in Chamba district, Himachal Pradesh. (PTI Photo)Seven passengers were killed and 11 others were injured after a private bus overturned and fell onto a lower road in Chamba in Himachal Pradesh on Saturday morning, police said.The accident occurred around 7.15 am near Chalunj Mor on the Bairagarh-Tissa road when the bus was travelling from Bairagarh to Chamba, reported news agency PTI.The accident took place on the treacherous 27-km mountain route through the remote Churah Valley, known for its narrow roads and steep drop-offs. The route is also a key stretch towards the high-altitude Sach Pass.Rescue operation is underway.