A teenager has been arrested alongside four adults as part of an investigation into right-wing terrorism.
All five - from southwest England, northern England and Wales - have been taken to a police station in West Yorkshire for questioning, according to Counter Terrorism Policing North East said.
The 16-year-old boy was arrested in Swindon, a town in Wiltshire, on Saturday morning.
He was arrested on suspicion of being concerned in the commission, preparation or instigation of acts of terrorism under Section 41 of the Terrorism Act 2000.
On Saturday morning, officers arrested a 29-year-old man, a 30-year-old man and a 28-year-old woman in Keighley in West Yorkshire as well as a 28-year-old man in Anglesey, a Welsh island, on the same offence.
A number of properties are currently being searched in connection with the arrests which form part of an ongoing investigation into right-wing terrorism.
Authorities said the arrests form part of an ongoing investigation into right-wing terrorism, which is being led by Counter Terrorism Policing North East.
In a statement, Counter Terrorism Policing - a collaboration of UK police forces that work with the UK intelligence community on terrorism - said: “We recognise that local people may have concerns as a result of this activity.
“We would like to reassure them that these arrests are pre-planned and intelligence led and there is not believed to be any immediate risk to the local community,” it added.
“We are grateful for the understanding, patience and support of local residents while these enquiries continue.”
Additional reporting by Press Association