King's Cross underground station had to be evacuated today after Belgian football fans set of flares as they headed to watch their team.

Standard Liege play Arsenal tonight and supporters of the east Belgium team poured into London this lunchtime ahead of the 8pm kick-off.

The fans congregated outside St Pancras, where Eurostar trains arrive from Brussels, and King's Cross, from where underground trains go toward to Emirates Stadium.

Red smoke from football fans' flares filled King's Cross St Pancras tube station today after Standard Liege supporters arrived in London en masse for tonight's game at Arsenal

Large groups of Belgian football fans arrived into St Pancras from Brussels this morning

Fans were seen chanting and setting off fireworks outside before they piled into the tube station, which had to be evacuated due to the smoke from flares.

Julia Silk tweeted: 'Very much hope the @metpoliceuk are going to arrest every single one of the massive crowd of utter hooligans who just let off a load of bangers at #kingscross in crowds including pregnant women and small babies then marched off chanting past St Pancras.'

Kifaya Omar added: 'Just had to run out of kings cross station and heard so many loud bangs and was worried it was a terrorist attack... but apparently it’s smoke bombs from football fans?'

Another Twitter user wrote: 'Got off the Victoria Line to be evauated out of Kings Cross Station immediately because football supports are letting off gas bombs in the station and outside... kids crying outside & people trying to rush ... it was manic.. luckily police were there to handle the situation well.'

Arsenal play Standard Liege in Group F of the Europa League this evening.