A pitch invasion which led to a football steward being trampled by a police horse has been labelled "completely unacceptable" by police chiefs, who vowed to prosecute the troublemakers.
The behaviour towards officers and match stewards from some fans at last night's cup tie derby between Preston North End and Blackpool was criticised as "disgraceful".
Police said "a significant minority of determined people" from both sides were intent on causing trouble on the night and added that those identified would be tracked down and prosecuted.
Two people were arrested for criminal damage to one of the supporters' coaches outside the ground, with another four people held for minor offences.
Superintendent Richard Morgan, of Lancashire Police, said police officers "responded quickly" to the pitch invasion at the end of the Preston-Blackpool match on Monday night. A steward was struck by a police horse during the disorder.
We are aware that a steward was injured inside the ground and I would like to reassure people that will be looking into the circumstances around how and why that happened.
We have been working closely with the football club in the lead up to and throughout the match. I would like to stress that it is only a minority who have been involved in the disorder with the majority of supporters enjoying the event and getting home safely.
John McDougall, who was reporting from the match for the Press Association, said: "It was a feisty game - not a dirty one - and there was clearly local pride at stake.
"At the end of the game there was a pitch invasion and some of the Preston fans went over towards the Blackpool supporters in the away end.
"Police, both on foot and mounted, formed a wall between the two sets of fans. It took about five or 10 minutes for them to clear the supporters.
"Both managers have condemned the pitch invasion."
Lancashire Police have confirmed they are looking into the incident.
A football steward appeared to be trampled by a police horse following a pitch invasion at the end of the Capital One Cup game between Preston North End and Blackpool tonight.
The steward, who was wearing a hi-vis jacket, was on the Deepdale pitch helping clear fans after the hosts' late winner prompted scores of supporters to run from the stands to congratulate the players.
But one steward appeared to be struck by a police horse as it cantered across the pitch, while another horse - also helping with crowd dispersal - seemed to clip the steward as he lay on the ground.
Tom Clarke headed the only goal as the League One side defeated Lancashire rivals Blackpool.
Blackpool Pleasure Beach have teamed up with Nick Park to create the world's first Wallace and Gromit theme park ride.
The family ride called Thrill-O-Matic features all of the characters from the animated adventures, as well as classic scenes from A Close Shave, A Matter of Loaf and Death and the Wrong Trousers.
This allegation, like any allegation involving the wellbeing of young people, is being taken extremely seriously and will be thoroughly investigated as our priority is the safeguarding of young people. We are in the early stages of this inquiry and are working closely with the school and the local authority to establish the circumstances. No arrests have been made at this stage.
The head teacher and five staff members at a primary school in Blackpool have been suspended as police investigate an allegation related to the treatment of pupils.
Blackpool councillor Sarah Riding, cabinet member for education and schools, said:
"We were made aware of an issue at Revoe Primary School that raised concerns to us about the professional judgement made by a number of staff in relation to pupil wellbeing.
“Although we have no reason to suspect any child has come to harm this is a serious situation that needed immediate action to be taken.
Lancashire Constabulary said the allegation was being taken "extremely seriously and will bethoroughly investigated as our priority is the safeguarding of young people".
A spokesperson said no arrests have been made at this stage.
The siblings of Sasha Marsden have made individual tributes to the murdered student:
Sasha was an adorable little sister and was never afraid to put her opinions across no matter what the situation was. She always knew how to make us smile, especially after winding us up. She gave the most amazing cuddles and we will miss her so much.
She is a gorgeous little lady and knows how to make an impression and when you meet her, you would never forget her. She was an expert wind-up merchant and although you might be annoyed with her, you couldn't stay mad with her for long.
Cheeky, friendly and stubborn are all things that make Sasha as special as she is and make her overcome anything. She is a beautiful sister and a wonderful and caring aunty too.
The family of Sasha Marsden will lay flowers at the scene of her brutal death in Blackpool at 5:30pm tonight.
Her parents, Gary, 40, and Jayne, 45, have paid tribute to their "beautiful daughter", who they lovingly described as a "typical teenager", in the following statement:
No words can express how we feel. Our beautiful daughter has been taken from us.
She was a loving daughter, sister, granddaughter, great granddaughter, auntie, niece, cousin and girlfriend. She was very much loved and her loss has left a huge gap in all our lives, a gap that can never be filled.
Sasha was your typical teenager, a fun-loving girl who enjoyed spending time with her friends and boyfriend, with her parents being last on the list unless she wanted something or needed a lift somewhere.
They asked for the family to be "left alone in private to allow us to come to terms with losing our beautiful precious daughter".
The family of a 16-year-old girl murdered in a frenzied stabbing have said her death "has left a huge gap in all our lives".
Sasha Marsden's body was found in a rear alley behind a bed and breakfast hotel in Blackpool, Lancashire, on Thursday night.
She had been repeatedly stabbed to the head and face before attempts were made to set her body on fire.
Detectives are continuing to question a 22-year-old local man on suspicion of her murder.