Thirteen people were killed on Saturday when an overcrowded bus skidded off the road and fell into a 100-metre deep gorge in Himachal Pradesh, police said.The vehicle was going to Tiuni in Uttarakhand from Hakoti in Shimla district when it fell into the gorge near Snail, some 65 km from the state capital.Ten of the victims died on the spot, a police official told IANS.Among the dead was a seven-year-old child.Witnesses said the administration had a tough time extricating the victims from the badly-mangled bus. The accident spot was seeing rainfall.Rescue workers said the road where the accident occurred was badly damaged and there was no parapet to prevent the vehicle from rolling down.Chief Minister Jai Ram Thakur and Governor Acharya Devvrat expressed grief over the accident.