Four people have been killed and three others injured when a commuter train hit them in Spain as they crossed the tracks outside of an authorised area, officials said.

The accident happened on Sunday when a group of seven people attempted to cross the railway line in Montmelo, about 20 kilometres north of Barcelona, emergency services in the northeastern region of Catalonia wrote on X.

"Firefighters searched for other possible victims near the train. They did not find any others. They also helped evacuate the area," the regional civil protection agency said in a statement.

Spanish media said the group was leaving a techno music festival that was taking place at the Montmelo race track, which is famous for hosting F1 racing events, on the eve of a holiday in Catalonia.

According to Spain's state rail infrastructure operator Adif and state-owned railway operator Renfe "a group of people crossed the tracks at an unauthorised point, in a curve of difficult visibility," the statement added.

Emergency services dispatched nine ambulances and a helicopter to the scene.

The roughly 170 people who were on board the commuter train did not require medical attention.

Series of accidents

"I am completely distraught by the multiple collision of a train at Montmelo, a tragedy that leaves us breathless," head of the regional government of Catalonia, Pere Aragones, wrote on X.

"Emergency services are continuing to work and offering support to the victims and their families. Police are investigating the causes of the accident," he added.

There have been several deadly accidents in recent years on Catalonia's suburban train system known as Rodalies, which regional officials have blamed on central government underfunding.

The Catalan separatist parties which govern the wealthy northeastern region have long complained the Spain's central government underfunds the system, leading to poor upkeep of the network.

In June 2010 an express train struck a group of people who were crossing the railway in the beach resort of Castelldefels, killing 12 people.

The people crossing the line on that occasion had just got off a commuter train and were crossing the track to get to the beach where a concert was being held to celebrate the summer solstice.

Some people complained at the time that an underpass exit was poorly marked and an old crossing was blocked off, leaving travellers confused.

But Spanish government officials insisted there were enough signs telling passengers how to safely reach the beach and that a loudspeaker service had warnings for passengers not to cross the tracks.