Frankfurt Police are investigating a video which appears to show stewards at the Euro 2024 showdown between Portugal and Slovenia punching and kicking a fan. The footage obtained by Portuguese media showed the altercation, which occurred while play was underway at Deutsche Bank Park.

It shows two fans being restrained by a group of stewards on Monday night, with one of them appearing to take multiple punches to the face while pinned up against the wall of a tunnel.

He then fell to the floor, where two stewards appeared to continue kicking and punching him. The other fan is pinned to the floor throughout.

A spokesperson for Frankfurt Police has now said: “I can confirm that we have knowledge of the incident and that we are investigating it.”

Portugal went on to win the game on penalties after the two sides remained deadlocked for 120 minutes. Goalkeeper Diogo Costa was the hero of the night as he saved three spot-kicks, following Cristiano Ronaldo’s miss from 12 yards earlier in the contest.

After an earlier Portugal game, against Turkey in Group F, UEFA pledged to beef up their security measures in light of numerous fans attempting to invade the pitch. Many of them targeted Ronaldo in the hope of getting a picture.

UEFA’s statement read: “Safety and security in the stadium, on the pitch and at team facilities are the ultimate priority for UEFA, DFB and EURO 2024 GmbH. To this end, additional safety measures will be deployed in the stadiums to further meet the requirements of the tournament, and to prevent such incidents.”

Portugal will be back in Euros action on Friday. The Selecao’s nervy win over Slovenia has set up a mouth-watering quarter-final with France at the Volksparkstadion in Hamburg.

While Portugal manager Roberto Martinez will be focused on making it through to the semi-finals, he took time earlier in the tournament to stress the importance of safety for his players. “It is a concern,” said the Spaniard.

“The intentions of the fans were good [against Turkey]. We all love a fan who recognises the big stars and icons. But you understand there’s a difficult moment if their intentions are wrong. We need to be careful. It shouldn’t happen – there’s a lot of security.

“We should send a message to the fans because it is not the right way. It may get worse for the future. It’s not good to have the players so exposed on the pitch.”