Portugal’s manager, Roberto Martínez, voiced security concerns after his team’s victory over Turkey was marred by five spectators invading the pitch and making their way to Cristiano Ronaldo in search of selfies.

A sixth man failed in an attempt to get to the five-time Ballon d’Or winner but caused a steward to slip and crash into the Portugal striker Gonçalo Ramos, knocking the Paris Saint-Germain player to the turf.

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The first pitch invader, a young child dressed in a red tracksuit top, was warmly received by Ronaldo, who waited for the boy to reach him, smiled, put his arms out and then posed for a picture together midway through the second half. But the Portugal captain was unimpressed when a second person, this time apparently in his early 20s, ran on and interrupted the game shortly after.

Two more supporters got on to the pitch during Portugal’s 3-0 win in Dortmund, the third a man in a Turkey shirt. The fourth, seemingly a teenager, dressed in black, ran across the six-yard box while Portugal were defending a corner late in the game. A fifth then came on upon the final whistle.

A sixth appeared while Portugal were heading off, having applauded supporters, a few minutes later. He slipped and got up again, eventually wrestled to the ground by five stewards. His behaviour caused the collision involving Ramos.

All six were taken away by stewards and the matter will be handled by German police. Uefa’s disciplinary body will await reports before deciding on any action. Responsibility for any fines and bans of the six individuals rests with the state authorities.

Ronaldo had been grabbed at the beginning of the Euros by a fan who was among a dozen supporters who ran on to the pitch at Portugal’s training camp in Gutersloh. The Wolves goalkeeper José Sá tackled one of them to the ground.

“It is a concern because today we were lucky that the intentions of the fans were good,” Martínez said here. “We all love a fan who recognises the big stars and the big icons in their life. We all agree with that. But there is a very, very difficult moments if those intentions are wrong – the players are exposed and we need to be careful with that.

“I don’t think that should happen on a football pitch. There is a lot of security and a lot of protection and it should not happen. And probably we should give a message to the fans that it’s not right way; you’re not going to get anything out of it and probably the measures will get worse for the future. It’s not good to have the players so exposed when people are running on the pitch.”

The boy who was the first to run on to the pitch took a selfie with Ronaldo, then dashed away from security staff, cheered by the crowd as he twisted and turned to escape them. Eventually caught, he was handed an ovation as he was led off, while security were booed. Supporters were less impressed with subsequent invaders, as was Ronaldo.

Stewards were a little quicker to react to the second invader and more physical in removing him. Ronaldo could see him coming and stood with hands on hips, his displeasure clear. As the supporter put an arm around Ronaldo’s shoulder, the 39-year-old pulled it off, with staff arriving to pull the man away. The fifth, who came on at the final whistle, appeared to plead with Ronaldo, who did not want the picture to be taken. A steward’s slip meant the sixth did not need to run to get on to the pitch.

Bernardo Silva, the scorer of the first goal, said he did not feel threatened by the invasions. “It’s just a bit annoying in terms of always having to stop the game because a fan enters the pitch,” he said. “But I think that’s the price you pay for being so recognised in the world of football and having a player like him with us. But in terms of feeling in danger, I don’t think so, no. Not me personally.”