With more than 280 people killed and hundreds more injured in a passenger train collision in India, questions are again being raised about the safety of India's rail system, which carries more than 12 million people per day.

Friday's incident was India's worst in over two decades, officials said.

Rail accidents are far from rare across the globe, with lax regulations, ageing infrastructure and human error all playing their part in disasters that have killed hundreds of people.

Here are some of the worst rail disasters of the past 10 years, and what caused them.

Passenger train hits freight train in Greece

On February 28, 2023, a head-on collision between a freight train and a passenger train on the route between Athens and Thessaloniki claimed 57 lives, in the country's worst rail accident.

The collision was attributed by the Greek prime minister "mainly to human error", and sparked violent protests across the country demanding better rail standards.

Stowaways derailed in DR Congo

On March 10, 2022, a freight train loaded with stowaways derailed in the Democratic Republic of Congo's Lualaba province, killing at least 75 people and injuring 125 others.

The crash was reportedly attributed to the train's locomotive struggling to deal with a steep slope.

A month later, at least eight people died when a goods train derailed in the same area.

Track faulty in Pakistan farmlands

On June 7, 2021, at least 63 people died when a train hurtling through farmland derailed and collided with another passenger service in Ghotki, in Pakistan's southern Sindh province.

An initial investigation into the cause of the crash determined it was the result of a faulty welding joint in the tracks.

Truck slides onto tracks in Taiwan

On April 2, 2021, at least 51 people were killed and 200 injured when a passenger train collided with a truck that had slid down an embankment near the city of Hualien — the island's worst rail disaster in decades.

The truck's emergency brake had not been properly engaged, causing the vehicle to slide about 20 metres down a hillside onto the track, where it was struck by the train minutes later.

Pakistan pilgrims die in gas fire

At least 74 people died and more than 40 were injured on October 31, 2019, when a fire broke out on an overcrowded passenger train carrying pilgrims to a religious gathering near Lahore.

The blaze was reportedly caused when some of the passengers tried to prepare breakfast on a gas cooking stove as the train was moving, in violation of railway rules.

Fireworks bring about 'freak accident'

A speeding train ran over revellers watching fireworks during a Hindu festival in northern India on October 19, 2018, killing at least 60 people and injuring at least 50.

Railways police said the "freak accident" happened when the sound of fireworks at the Dussehra festival, on the outskirts of Amritsar, made it impossible for people to hear the commuter train bearing down on them.

Track behind Indian Express disaster

At least 146 people died when an Indore-Patna Express train with around 2,000 people on board derailed near Pukhrayan in Uttar Pradesh on November 20, 2016, sending carriages crashing into each other.

The impact was so strong that one of the coaches landed on top of another, crushing the one below.

Officials hinted a broken track may have been to blame for the disaster.

Spain crash followed high-speed approach

About 80 people were killed and about 140 injured when a high-speed train slammed into a concrete wall near the north-western city of Santiago de Compostela on July 24, 2013.

The train had been approaching a curve at more than twice the speed limit.

AFP/ABC