Police say they are reviewing three further incidents, including the stabbing of a 14-year-old boy, after a man appeared in court in connection with a mass knife attack on a train.
Anthony Williams has been charged with 11 counts of attempted murder over Saturday's mass stabbing, and another attack hours earlier at a London station.
The 32-year-old, of no fixed abode, was remanded in custody on Monday when he appeared at Peterborough Magistrates' Court.
Williams has been charged with 10 counts of attempted murder, one count of actual bodily harm and one count of possession of a bladed article following the attack on the Doncaster to London King's Cross LNER service.
Scunthorpe United confirmed their defender Jonathan Gjoshe was among those hurt and is in hospital with non-life-threatening injuries.
The train driver who led an unscheduled stop at Huntingdon station as the incident unfolded has since paid tribute to his colleagues.
In a statement, Andrew Johnson, who is ex-Royal Navy and has been driving trains for almost 20 years, said: "As train drivers, we hold a lot of responsibility. We practise our emergency response and keep up to date with our knowledge of the route, so if needed, we know exactly where to stop and what to do."
He added: "The action I took is the same as any other driver. I think my colleagues onboard were the real heroes and I'd like to pay tribute to their bravery."
Earlier, British Transport Police (BTP) said Williams had also been charged with another count of attempted murder and possession of a bladed article in connection with an incident on a London train in the early hours of 1 November.
The force said a victim suffered facial injuries after being attacked at 12.46am with a knife on a train at Pontoon Dock station on the Docklands Light Railway (DLR) in east London.
The suspect had left the location before police arrived and officers subsequently identified Williams as a suspect, the force added.
Meanwhile, Home Secretary Shabana Mahmood said police in Cambridgeshire were investigating whether the same man committed "further offences" earlier.
Police there said they were looking at a series of incidents on Friday and Saturday, including one in which a teenager was stabbed.
In a statement, Cambridgeshire Constabulary said a barbers in the Fletton area of Peterborough reported a man with a knife on Friday evening, and again on Saturday morning when police were not able to locate the suspect.
A third incident "that police also believe may be linked" involved a 14-year-old who was stabbed on Friday evening by a man with a knife in the city centre, the statement added. The teenager suffered minor injuries.
The force has referred itself to the police watchdog.
British Transport Police will include the stabbing of the 14-year-old and the incident at the barber's shop as part of its investigation into the train attack.
Armed officers were deployed to Huntingdon, Cambridgeshire, on Saturday evening where the LNER train was stopped and detained Williams within eight minutes of the first 999 call.
Footage of his arrest has emerged, showing a man on the ground surrounded by officers and a barking police dog, with the sound of a Taser being deployed.
Another man, also detained, was later released after officers established he was not involved.
Prosecutor: Williams is 'risk' to public
Williams wore a grey tracksuit when he appeared in court on Monday in handcuffs. He spoke softly to confirm his details and when asked his address, mumbled "no fixed abode". He was not asked to enter pleas.
Opposing bail for Williams, prosecutor Olaide Esan told the hearing: "The defendant has attempted to murder 11 people in total. These are serious allegations. These are very serious offences.
"The defendant is a risk to the trains and to the members of the public."
He allegedly used a "large kitchen knife" in both attacks, according to court documents.
The court heard Williams faces an assault charge after allegedly attacking a male police officer in custody, leaving him with a "broken nose", Ms Olaide said.
Williams is due to appear at Cambridge Crown Court on 1 December.
Minister: Rail worker was a 'hero'
On Monday, Transport Secretary Heidi Alexander told Sky News that one man, originally suffering life-threatening injuries, was now in a critical but stable condition in hospital.
She told Mornings with Ridge and Frost programme: "He went in to do his job, and he left work a hero. And there are people who are alive today because of his actions and his bravery."
On Sunday, British Transport Police (BTP) confirmed he was a member of LNER rail staff who tried to stop the attacker.
"Having viewed the CCTV from the train, the actions of the member of rail staff were nothing short of heroic and undoubtedly saved people's lives," said BTP Deputy Chief Constable (DCC) Stuart Cundy.
The train driver, named as Andrew Johnson, has also been hailed as "courageous" for his actions during the stabbings.
Read more from Sky News:
Major incident declared in Cumbria
British teen sentenced over drugs charges
Air India survivor says trauma 'broke' him
Ms Alexander also told Sky News that BTP would be "increasing the visible patrols at stations" over the next few days.
"But generally, our trains are some of the most safest forms of public transport anywhere in the world," she added.
(c) Sky News 2025: Police reviewing three further incidents - including stabbing of boy, 14 - after train knife attack
'Heroic' staff commended after Huntingdon train stabbing as details of victims emerge
Ryanair boss hits out at chancellor over growth as profits climb 42%
Only survivor of Air India Flight 171 crash tells Sky News the trauma 'broke' him
Nigel Farage says Reform UK could cut minimum wage for young people - and defends U-turn on tax pledges
Torre dei Conti: Worker trapped after medieval tower collapses during renovation work in Rome
Rickshaw driver spared jail after stealing £31,000 worth of wine and champagne from restaurants
Pregnant British teenager held on drugs charges freed from Georgian jail
Headteachers' union considering industrial action after losing High Court bid against Ofsted