An American tourist has been stabbed while protecting two women from a violent assault on a tram in Germany.

The male has been identified as a part-time model and a newly qualified paramedic from upstate New York.

John Rudat, 21, was travelling in Dresden early Sunday when he stepped in as two women were being attacked by a pair of men, according to a GoFundMe set up by his brother’s girlfriend, Molly.

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Mr Rudat was hospitalised with knife wounds to his face after bravely intervening.

“We got a little scared when we found out,” Molly, a fellow first responder, told The New York Post.

“We didn’t know the extent of his injuries. We were at dinner the other day and he called saying, ‘Hey, I’ve been in an incident, I’m OK, just if you can notify my parents because they weren’t answering the phone.’”

Mr Rudat had been staying in Dresden with his former foreign exchange host family when, according to the videos he later posted on social media, he crossed paths with a well-known local thug and drug dealer.

Pictures from the aftermath show blood splattered across the tram floor, with tissues scattered everywhere used by passengers to try to stem his bleeding.

It has been reported that one of Mr Rudat’s suspected attackers was a 21-year-old Syrian national, who was arrested on suspicion of beating him before his accomplice stabbed him.

Prosecutors later released this man.

“According to the on-call public prosecutor’s assessment, there were insufficient grounds for detention. The knife attack cannot be attributed to him,” Senior Public Prosecutor Jürgen Schmidt told a German news outlet.

Bloodied and bandaged across the nose and mouth, Mr Rudat posted to Instagram on Sunday night to condemn his attackers and rail against what he described as Europe’s immigration problem.

“If y’all didn’t think Europe had an immigration problem, especially Germany, let me drop some knowledge on you,” he said.

“It is 11:57am right now. In three minutes, that man that assaulted that young woman will be released from custody. He’ll be released from custody because he’s not a citizen of Germany, he’s not a citizen of the EU for that matter.

“He’s an immigrant, an illegal one, a drug dealer, and very popularly known here, especially by the police. This is not the first time this has happened. It’s not the first time that man has beaten up women, and it’s not the first time that the other guy decided to take a swing at my face with a six-inch blade.

“If they could do this to the people of Germany and then just get released 12 hours later — even less at this point — where is the law? Where is the structure?

“If Germans are held to that law and that structure, but these people could just come in, swing knives and hurt, abuse, terrorise and oppress citizens of Germany, then what do we do?” he asked.

From the family home outside Albany, New York, Mr Rudat’s brother, Logan, said he wasn’t shocked to hear about his sibling’s actions.

“I would have been surprised if he hadn’t stepped in,” Logan, 22, also a first responder, said.

“It’s part of his character. That’s just the way we were raised,” he said, adding he hoped Mr Rudat would be able to return to the US in the next week or so.

The US Embassy in Germany issued a statement urging authorities to bring Mr Rudat’s attackers to justice.

“We urge German authorities to swiftly bring the perpetrators to justice and punish them to the fullest extent permitted by law. Safety is a collective responsibility — no one is safe until all are safe,” the Embassy said