Two boys, aged 12 and 13, remain in hospital after a suspected street knife attack which left them both with serious injuries.
Police arrested a 43-year-old man following the incident at the junction of Southleigh Road and Eastleigh Road in Havant, Hampshire, at around 3pm yesterday, and he remains in custody.
A Hampshire Constabulary spokesman said: "Two local children have been hurt and are being treated for injuries believed to have been caused by a knife.
"Following clarification from the families we can confirm that a 13 year-old boy who was taken to Southampton General Hospital with life-threatening injuries, remains in hospital. His condition is now described as critical, but stable.
"A 12 year-old boy who was initially taken to Queen Alexandra Hospital, at Cosham for treatment has now been moved to Southampton General Hospital. His condition is still described as serious, but stable."
Extra police patrols have been deployed in the area this weekend, but officers said the incident was being treated as "isolated".
Chief Inspector Patrick Holdaway said: "My thoughts go out to the children who have been hurt and their families. We're providing assistance to them at the current time and both children are being treated in hospital for their injuries.
"We'd like to reassure the local community that no-one else is being sought in connection with this assault at this time.
"Thankfully no-one else was hurt in the incident and there is no further risk to members of the public.
"Our inquiries indicate that a school in the local area had an inset day, so there were not large groups of parents and children in the area when the assault happened.
"Local officers will also be patrolling across the weekend and will be speaking to local residents to keep them informed."
Police were last night speaking to witnesses and appealed to anyone who may have seen anything out of the ordinary in the area to come forward.
A police spokesman said: "Police deployed immediately to the scene and a 43-year-old man of no fixed address was arrested.
"He has been taken into custody and detectives have commenced an investigation."
Anyone with information is asked to call Hampshire Constabulary on 101, quoting Operation Narrow.