Officers from Thames Valley and the Metropolitan Police today (25/12) responded to a security breach at around 8.30am within the grounds of Windsor Castle, which is under the control of the Met.
A 19-year-old man from Southampton has been arrested and he remains in custody at this time.
Thames Valley Police Superintendent Rebecca Mears, said: “An investigation is ongoing following this incident and we are working with colleagues from the Metropolitan police.
“The man has been arrested on suspicion of breach or trespass of a protected site and possession of an offensive weapon. He remains in custody at this time.
“We can confirm security processes were triggered within moments of the man entering the grounds and he did not enter any buildings.
“Members of the Royal Family have been informed about the incident.
“We do not believe there is a wider danger to the public.”