BIRMINGHAM, England (AP) — English police had 46 supporters of Legia Warsaw in custody Friday after “ 90 minutes of sustained violence ” the night before when 1,000 Polish fans arrived to Villa Park but weren’t given their tickets to the game against Aston Villa.

West Midlands Police said their investigation will include determining why the tickets weren’t distributed but that they’ll pursue charges against those arrested after four officers were injured.

“The disorder that we encountered last night was the most severe that a lot of us have ever seen,” assistant chief constable Damian Barratt told Talk Sport radio.

“It was undoubtedly, as I say, instigated as a result of this issue related to ticket allocation,” he continued. “That’s something I’ll be taking up with football authorities and UEFA in particular. I will be expecting some strong decisions on their part.”

Villa won the Europa Conference League game 2-1. The away fans section of the stadium was empty.

UEFA said Friday that it “strongly condemns the unacceptable violence” that took place.

“UEFA is in the process of gathering all official reports from the game before deciding on potential next steps,” the governing body said in a statement. “We have no further information or other comment to make at this stage.”

The normal process of ticket allocation, Barratt explained, is that the home club through UEFA provides them to the away club.

“Unfortunately that didn’t happen. As a result, it wasn’t that we excluded fans, it was that there were no fans with tickets that we could potentially safely facilitate into the ground and for that reason we had to make the decision in conjunction with the club that the turnstiles will not be opened,” Barratt said.

The Polish fans had been instructed to come to the stadium to receive their tickets and be escorted inside by police.

Aston Villa and Legia Warsaw did not return emailed messages Friday seeking comment.

The Polish team on Thursday night blamed Villa for “refusing to allocate tickets to away fans.”

Barratt described “enormous hostility” among the estimated 1,000 away fans, some of whom started fires and threw flares. Police did not indicate that their officers’ injuries were serious.

Most of the arrests were for violent disorder, four for “possession of a knife/offensive weapon,” and four for assaulting emergency workers,” police said.

“All of those arrested are away fans, and we’ll be working hard to charge and remand those suspects where we can today,” West Midlands Police said in a statement on Friday.