Burnley's pre-season friendly at home to German club Hannover was abandoned on police advice after crowd trouble.
Trouble broke out in the first half in the Hannover fans' section at Turf Moor on Saturday.
Burnley, who had been leading 1-0 after a header from Ben Mee, announced at half-time that the game had been abandoned.
"We went on police advice. We are still piecing together the details," said Burnley manager Sean Dyche.
Seats were ripped up and thrown after visiting supporters surged towards the home fans in the Cricket Field Stand around five minutes before the end of the first half.
Home supporters were moved from the stand as police moved in. The players did not appear for the start of the second half with the decision taken to abandon the match.
Chief Superintendent Chris Bithell, of Lancashire Police, said the decision was taken "following consultation between the police match commander, the referee and Burnley FC's grounds safety officer".
He added: "This follows violent behaviour by a group of travelling Hannover fans, who attempted to attack fans in the home stands, as well as police officers and stewards."
Dyche added: "The referee came to see me and said he wanted us in the room just to get a feel for our general thoughts."
"I made it clear. It comes down to safety. The police decided to call it off and we support that.
"We understand that. It's important what the team do, but it's not as important as people coming to a football match. You want safety. You don't want people to get hurt.
"It's a shame what has happened but it's done, as simple as that.
"In the bigger picture I think the lads are fit and well. I think they've shown some good signs in pre-season and I think there's still more to come."
On Saturday night, Hannover released a statement condemning the behaviour of their fans.
"Our attitude is clear: Hannover 96 condemns the incidents in the stadium and dissociates itself vehemently from any kind of violence," the club said.
Burnley start their Premier League campaign away to champions Chelsea on 12 August.