A 21-year-old man has been arrested in connection with the stabbing of schoolgirl Jessica Knight, Lancashire Police said today.
Chief Superintendent Irene Curtis announced the arrest in an interview with GMTV.
Jessica, 14, suffered multiple knife wounds after being attacked while walking through Astley Park in Chorley, Lancs, at around 5.15pm on Monday.
She is now fighting for her life in hospital amid reports she may have been stabbed up to 30 times.
Screams rang out, alerting members of the public, and a cyclist in the park found the youngster "covered in blood".
Two other people walking in the park helped the stricken teenager, who was given first aid before being rushed away by ambulance.
Jessica underwent five hours of emergency surgery at Chorley Hospital after the attack and is now in a stable, but critical, condition with her family at her bedside.
She was spotted by the cyclist lying unconscious on the pathway in the park.
A second man, Simon Corlson, 52, a project manager, dialled 999 on his mobile phone and then fetched a blanket from his car.
He said: "A policeman told me later that she'd been stabbed 30 times.
"But I only saw two of the wounds - one to her cheek, the other to her neck, pumping blood."
Police had warned residents to beware while the attacker was still on the loose.
Det Supt Steve Brunskill, leading the manhunt for Lancashire Police said Jessica had been spotted on CCTV visiting a local shop at around 5pm, before going to the park, a gathering place for youngsters.
He added: "This incident is extremely rare. This is a particularly nasty violent attack on a defenceless 14-year-old girl.
"I can't think of any motive. Until we find whoever is responsible, people should be cautious. The circumstances of it are we think it's a random attack.
"It is not a particularly discreet area, it's overlooked by properties on both sides and it's well-lit."
He said there was nothing in Jessica's background to suggest a motive and it was not a sex attack.
"The family are very distressed. As far as we are aware, this is a perfectly normal, happy child. It's mind-boggling how this can occur in this area.
"We are particularly interested in speaking to anyone in the area at that time. It is a busy time, people are walking dogs and coming home from work," he added.
Jessica was wearing a black hooded jacket with fur lining, blue jeans and white trainers.
He asked for anyone who saw anything suspicious in the area over the last few weeks to come forward.
"I'm also interested in speaking to anybody who knows a person who came home on Monday in an agitated state or who may have been blood stained," he said.
"I am particularly interested to hear from anyone who may have seen any suspicious behaviour.
"At this early stage of the investigation we are unsure of the motive and would urge people in the area to take precautions for their own safety until this dangerous offender, or offenders, is caught."
Jean McGrath, head of Parklands High School in Chorley, where Jessica is a pupil, said, "We were all shocked and distressed to hear of the attack on Jessica.
"Her grandfather rang me at the school this morning and informed me and I went straight to the hospital where I spent time with her parents.
"I spoke to all our pupils telling them of the incident, thinking and praying for Jessica and reminding them to be extra vigilant with regard to their own safety.
"Jessica is a lovely, hard working girl. We hope and pray she will recover soon."
Detectives are now with the girl's family at the hospital waiting to speak to the teenager to try to piece together what happened.
Extra officers, including mounted officers and neighbourhood policing teams, will be on patrol in the area to reassure the public.
Forensic scenes of crime officers are now working to search the crime scene, a white tent covering the spot where the girl was attacked.
The area has council offices on one side and sheltered housing on the other. Astley Village is an affluent, semi-rural area north of Chorley.
Police stressed it was a low-crime area.
Laura Lennox, a councillor with Astley Parish Council, said, "It's not a path I would use on my own at night. It is very tragic that this should happen."
Don Cooke, 72, a retired train driver who lives in sheltered housing overlooking the crime scene, said, "I'm shocked to hear what's happened. School children cut through the park to go to school. We are used to hearing girls screaming and shouting so we don't take much notice."
Local resident Duggy Hope said locals had wanted the path through the park to be lit - but the local council decided not to.
"We have gangs of kids getting up to mischief but it's not bad around here. This is very rare. We have never seen anything like this before.
"They were going to put lighting up through the park but Chorley council knocked it back. There's a petition up about it."
Mr Hope's son, Matt, is in the same year as Jessica at her school.
He said, "I'm friends with one of her best mates, she was devastated, she was saying, 'Why would she walk through the park on her own?' Who would do such a thing?"'
The youngster said she was a popular girl with many friends. He said the friend told him Jessica had been listening to her iPod when she was attacked and stabbed 10 times.
A Lancashire Police spokesman said the 21-year-old man had been arrested on suspicion of attempted murder.
He said Jessica's condition was "critical but stable" today.