Pakistan has an appalling road safety record, with frequent accidents due to poorly maintained routes and vehicles - as well as reckless driving.
At least 20 people have died and 13 injured when a passenger bus plunged into a ravine near a small town in Pakistan's southwest.
Mahtab Shah, assistant administrator for the district of Shirani in Balochistan province, said about 35 passengers were traveling in the bus on Sunday.
He said rescue workers were searching for survivors in the wreckage of the destroyed vehicle and surroundings.
Shah said apparently the bus slid on the wet road amid heavy rain and the driver lost control of the vehicle, which fell about 61 metres into the ravine.
The province is home to several Chinese projects under an investment plan in which Beijing is seeking road and sea trade linkages with the world.
Deadly road accidents are common in Pakistan due to poor road infrastructure and disregard for traffic laws, as well as poorly maintained vehicles.
Last month, 22 people were killed in a similar accident when a bus fell into a ravine in Qila Saifullah district.