Violence has erupted in Prague as West Ham fans were attacked with ‘fireworks and weapons’, with witnesses saying the incident was ‘completely unprovoked’.

Football fans headed to Prague, Czech Republic to watch Fiorentina take on West Ham in the Europa Conference League final clash this evening.

However, ahead of the match, the city’s streets turned to mayhem as fighting broke out, with reports of West Ham supporters being stormed by the ‘far-right Fiorentina ultras’.

Police of the Czech Republic tweeted to say that Italian fans had attacked West Ham supporters, saying three people have been injured.

A police officer was also assaulted, the force said, adding that 16 people had been detained.

A tweet automatically translated from Czech said: “Italy fans attacked West Ham fans in a bar in Rytířská Street, injuring three. One policeman was also attacked. We have restricted the personal freedom of 16 people and we are currently investigating the whole incident.”

The tweet was accompanied by a photo of several people lying on the floor of shoe stop, their hands bound behind their backs as officers stood guard over them.

An earlier statement had said: “Thousands of football fans mainly from Italy and England came to watch today's final match of the European Conference League. Even for us, this is an extremely demanding security measure, in which hundreds of police officers will participate.

“Policemen from anti-conflict teams who have experience in communicating with crowds of football supporters, including foreign ones, will play a key role. We wish everyone a wonderful sporting experience.”

Sky News sports correspondent Rob Harris tweeted a footage of the chaos on the streets, writing: “Prague: @skynews obtains video of fighting ahead of West Ham-Fiorentina #UECLfinal with eyewitnesses later saying a group of Italians with fireworks and weapons attacked West Ham fans leading to fighting and street covered in broken glass.”

A number of eyewitnesses also told the Daily Mail about the ‘grim’ scenes that unfolded, with one saying: “They targeted a group and attacked them quite violently then ran off before anyone could react. It was completely unprovoked.

“They were all ultras dressed in black. It was pretty grim.”

Retired plumber John Brownlie, from Cambridge, added: “From nowhere about 100 men with chains, belts, bottles, and flares came round the street corner, and almost pushed over a lady and her baby in a pushchair.

“The woman quickly was quickly rushed inside to the bar, with her child, but two stun grenades were thrown in there, and caused some fire damage.

“This caused a lot of us to come out of the bar to find out what was going on, and then they started attacking us, punching and kicking us. When they ran, which would've been probably a minute later, we ran after them but the police blocked us.”

He added: “They were just cowards. West Ham fans didn't do anything wrong. This was an ambush.”