Italian transport unions, consumer associations and Rome residents have called for a full investigation into the maintenance and safety of the city’s metro system after 24 CSKA Moscow football fans were injured when a crowded escalator suddenly sped up before collapsing.

Video footage showed people hurling down the rapidly moving staircase at Repubblica station before piling on top of one another at the bottom. One man is at risk of losing his foot while others suffered leg injuries after becoming trapped between the metal plates of the escalator’s steps.

An investigation has been launched by Rome’s public prosecutor and Atac, the company that manages the city’s transport system.

“The problem seems to have been due to an overload on the escalator,” said Michele Frullo, from the USB union. “We ask for maintenance works carried out by external companies to be monitored; for some time now we have called for such fundamental Atac jobs to be internalised.”

Claudio De Francesco, the Sicel union secretary for the Lazio region, said metro staff must be fully equipped to deal with all kinds of emergencies and that the system also needs “investments and operational strengthening”.

Codacons, the consumers’ association, said in a statement: “Given the gravity of the incident, Atac and the Rome authorities must immediately begin checks on the escalators running at all metro stations.”

The incident happened as the fans made their way to Rome’s Olympic Stadium for CSKA Moscow’s Champions League match against AS Roma. Italian media reported that the escalator broke after the singing and chanting group started to jump up and down on it. Matteo Salvini, the far-right interior minister, also put the incident down to “dozens of drunkards making a big mess”.

But a Russian woman who was with the group told reporters that the fans were not jumping. “Some were singing, but what does that have to do with it?” she said.

A source from Atac alleged in La Stampa newspaper that the cause was probably due to “maintenance negligence” and that a steel cable within the brake device that is supposed to prevent the escalator from unrolling may have failed. The escalators in operation within Rome’s metro have a lifecycle of 30 years; the one at Repubblica was less than 10 years old.

Similar incidents in the past have been fatal: in 2015, a four-year-old boy died after falling down an elevator shaft at Furio Camillo metro stop, while in 2003 a British woman was killed when an escalator collapsed at Tiburtina railway station.

The incident comes as Rome residents prepare to protest on Saturday against myriad issues blighting the city.

“As we await outcome of the investigations, bewilderment among Rome residents is increasing,” said Emma Amiconi, one of the organisers of the demonstration. She said residents wanted to know whether escalator maintenance was correctly carried out, but also what preventive measures were being taken to prevent vandalism on the metro.

“Without prevention and maintenance, a city like Rome cannot survive. We want a welcoming, safe and hospitable city.”