A passenger train has derailed in southern Pakistan, killing at least 40 people and injuring up to 100.
Wreckage still burns 12 hours after an Iranian train explodes
The BBC News website looks at some of the worst rail disasters to have happened round the world in recent times.
2007, DR Congo - At least 100 people are killed and scores more injured when a train's brakes fail in the south of the country.
Rail officials say the train, which was carrying goods and passengers, picked up speed when the brakes failed and seven carriages overturned.
2005, India - One hundred people die when a passenger train derails in floods in southern India.
Seven out of 14 coaches are derailed and at least three fall into flood waters after a bridge collapses.
2005, Pakistan - Three passenger trains collide near Ghotki in the southern province of Sindh, killing at least 132 people and injuring hundreds.
Police said a train travelling to Karachi crashed into a broken-down train, catapulting carriages across the track into the path of another train.
2005, Japan - More than 100 people are killed when a commuter train slams into an apartment block in the western city of Amagasaki.
About 450 people are also injured in the incident, which is Japan's worst since a train collision killed 161 people near Tokyo in 1963.
2004, Sri Lanka - Up to 2,000 people die when a train is engulfed by the Indian Ocean tsunami at Telwatta, 110 km (75 miles) south of the capital Colombo.
More than 1,500 people were on the train, bound for the southern city of Galle, but they were joined by hundreds of villagers who jumped aboard to avoid the tsunami.
Bodies were still being recovered months after the December tragedy, thought to be the world's worst train disaster.
2004, North Korea - At least 150 people are killed and 1,300 injured when a train hits a power line near the Chinese border, igniting wagons of oil and chemicals.
More than 30 public buildings and homes for 8,000 families are destroyed.
2004, Iran - Nearly 300 people are killed when train wagons break free and roll about 20km (12 miles) before derailing and catching fire.
Villagers gather to watch, but there is a huge explosion.
Iranians ask how such a volatile cargo - including sulphur, petrol, fertilisers and cotton wool - could be transported in the same convoy.
2002, Tanzania - Nearly 300 die when a passenger train carrying more than 1,200 people loses power on the brow of a hill near the capital, Dodoma, and rolls back at high speed into a freight train.
The driver and guard are accused of not applying the brakes quickly enough.
2002, Egypt - A train catches fire after leaving Cairo for Luxor, killing 373 people.
The train is packed to twice its capacity, and more than 100 bodies are so badly burned they cannot be identified.
1999, India - As many as 285 are killed when an express train bound for Delhi hits another train head-on at Gaisal station, in the state of West Bengal, at 1.30am.
Rail disasters are common in India, where the system is overstretched
1998, India - Some 201 passengers are killed in Punjab state, when the Delhi to Amritsar service derails and is hit by the Jammu to Calcutta train, travelling in the opposite direction.
1995, India - In Uttar Pradesh around 300 die and more than 400 are injured after two express trains collide near Agra.
1994, Angola - Faulty brakes cause a train to plunge into a ravine in Tolunda, Angola, killing 300.
1991, Pakistan - A train carrying 800 passengers from Karachi to Lahore hits a parked freight train at Ghotki, killing more than 100 people.
1990, Pakistan - A passenger train strikes a stationary freight train in Sindh Province, killing more than 210 people.
1989, Russia - In what is thought to be Europe's worst rail disaster in recent years, about 400 are killed near the town of Ufa.
A gas explosion erupts beneath two trains carrying more than 1,200 people.
1981, India - In Bihar, 800 people are killed when a cyclone blows a train into river.
It is thought to be the worst of many disasters on India's extensive but overcrowded rail network.