Many of the people aboard an intercity passenger train that collided with a freight train were university students heading to the northern city of Thessaloniki from Athens after a long public holiday weekend.

The impact caused a fire in a number of the passenger carriages, burning many commuters who were rushed to hospitals.

The mistake has caused an uproar in Spain since it was first revealed in the media in early February, with the country expected to go the polls at the end of the year.

About 50 cars actually left the tracks, 20 of which carried hazardous materials, reports say.

As tensions rise in the euro zone's second-biggest economy, strikes have spilled over into other parts of the energy sector, where maintenance work crucial for Europe's power supply will be delayed.

Train crossings had been on hold since April 29, when China suspended services with North Korea following consultations due to Covid-19 infections in its border city of Dandong.

One person has been killed and police have arrested more than 300 protesters.

While grateful for Europe's welcome, many find themselves unable to start a new life abroad.