Horror footage of people shouting 'there's kids under there' after Lisbon tram crash kills 15 and injures 23 more

The Portuguese capital has been left reeling following a fatal funicular derailment which left 15 people dead.

Another 23 were injured - including one child and five who are in a serious condition - when the carriage called The Gloria careered off the track and hit a building in Lisbon.

Three days of mourning have been declared for the victims of the 'tragic accident' that took place on Wednesday (3 September) evening, the city's mayor Carlos Moedas said.

Portugal as a whole is also observing a day of national morning today (4 September).

According to eyewitnesses, the famed yellow funicular - which is a tourist attraction in its own right thanks to its rich history which dates back 140 years - was seen hurtling down a street.

People were left trapped among the wreckage of The Gloria (PATRICIA DE MELO MOREIRA/AFP via Getty Images)

The funicular then smashed into a building near the Avenida da Liberdade, trapping several of those onboard in the wreckage.

It is not yet clear how many people were travelling in the carriage at the time of the crash.

One bystander told the Portuguese TV channel SIC that the funicular pelted past them 'at full speed', as per the BBC, adding: "It hit a building with brutal force and collapsed like a cardboard box; it had no brakes."

Footage of the incident which has been circulating online shows how onlookers rushed to free those trapped under the debris, with one chillingly shouting: "There are kids under the tram!"

Another can be seen gesturing towards what is left of the funicular and saying: "It just f*****g smashed."

Take a look at this:

Emergency workers were working to free people for a number of hours, but authorities later confirmed that everyone trapped has been rescued.

The nationalities of those who lost their lives in the funicular crash have not yet been disclosed by officials but it has been announced that some tourists are among the dead.

The UK Foreign Office said it is in touch with authorities in Lisbon and is ready to 'provide consular assistance if there are any affected British nationals'.

Investigators are now working to establish the cause of the deadly incident which occurred at 6pm, the beginning of Lisbon's evening rush hour, last night.

The funicular, known as the Elevador da Gloria, was opened way back in 1885 before being electrified 30 years later.

The mode of transport is classified as a national monument and it can carry more than 40 people, seated and standing. It is commonly used by Lisbon residents but proves extremely popular among tourists too.

Two carriages harnessed by steel cables run parallel to each other as they shuttle up and down the hill for a few hundred metres on a curved, traffic-free road.

More than a dozen people are dead (Zed Jameson/Anadolu via Getty Images)

Lisbon's mayor Moedas said yesterday: "It's a tragic day for our city... Lisbon is in mourning, it is a tragic, tragic incident."

Portugal's Prime Minister Luís Montenegro has scrapped his agenda for today (4 September) in wake of the devastating funicular crash.

President Marcelo Rebelo de Sousa also shared his 'sympathy and solidarity with the families affected by this tragedy'.

The government also shared a statement paying tribute to the victims and saying: "A tragic accident caused the irreparable loss of human life, which left in mourning their families and dismayed the whole country."

The funicular was operated by Carris, a company responsible for running public transport in Lisbon.

The firm has since spoken out to say it is 'very sorry about what happened' and that they 'need to get to the bottom' of what went wrong during the journey.

Carris shared a statement claiming that the correct maintenance had been carried out on the funicular.

The cause of the crash currently remains unclear.