Missiles were thrown at police as the visiting fans were held in the coach park near the stadium, before they were due to enter for the start of the game.

West Midlands Police said four officers were injured and although the game started on time, no Legia fans were allowed into the stadium ahead of kick-off.

The force said in a statement following the game that 39 people were arrested after the “disgusting and highly dangerous scenes”, with one of the injured police officers taken to hospital.

Two police horses and two police dogs were also hurt.

Chief Inspector Tim Robinson said: “This should have been a great evening of football which was enjoyed by fans from both clubs.

“Unfortunately, there were appalling scenes which saw away fans dangerously throw flares and other missiles at our officers.”

He said the “extreme violence” left police with no other choice but to prevent away fans entering the stadium, adding: “The safety of everyone is our priority, and clearly we had no other option.”

Villa and West Midlands Police both released statements before the game had finished, with the Premier League club revealing requests to the Polish club before the tie for help in preventing ticketless fans from travelling went unanswered.

Villa said: “Aston Villa Football Club can confirm that no away fans were allowed into Villa Park for this evening’s UEFA Europa Conference League fixture with Legia Warsaw on the advice of West Midlands Police following large-scale disorder outside the stadium caused by visiting supporters.

“The UK safety authorities, UEFA and Aston Villa, communicated on November 2 that the ticket allocation for away fans for this fixture would be reduced to 1,002 on the advice of safety authorities as a result of previous large-scale disorder caused by Legia fans last month at AZ Alkmaar.

“A number of Dutch police officers were injured during that disorder. As a consequence, UEFA banned Legia supporters from travelling to Mostar for their game against HSK Zrinjski.

“In spite of numerous requests for cooperation from Legia Warsaw concerning their travelling supporters, especially in the last two days, no assistance on the serious safety matter of away fans attending Villa Park was forthcoming from the visiting club.

“The club has repeatedly, including this morning, raised concerns in conjunction with UEFA and all the relevant authorities to Legia that ticketless away supporters were attempting to attend Villa Park.”

Villa said Legia fans “engaged in planned and systematic violent acts against West Midlands Police officers” about an hour before kick-off.

The club added: “Aston Villa strongly condemns the behaviour of those visiting supporters and would like to thank West Midlands Police for their professionalism in very difficult circumstances.”

In its own pre-game statement, the Polish side accused Villa of restricting access to their fans in a move it called “counterproductive and baseless”.

It said senior executives, including the club’s owner, made the decision to boycott the game in response to the move.

Legia coach Kosta Runjaic refused to be drawn on the disorder in the post-match press conference.

He said: “I think its a different topic, it’s not my business. I’ve been in a big focus to lead the team. We represented Polish football in a good way, all other things outside the stadium I don’t want to comment.

“We have great fans, they support us home and away. We can always count on them. So far since I’ve been at Legia I’ve had a good experience with our fans. I don’t know the content of it all happening.

“I don’t know the details, which is why it’s better I don’t speak too much about it. Unfortunately our fans weren’t in the stadium and the atmosphere would have been better.

“It’s not about the fans, it’s a pity but we can’t change it.”