A protester appeared to spark a fire outside Buckingham Palace gates before being hauled to ground.
Footage of the incident showed a small blaze outside the gates under the cover of darkness.
Met Police said in a statement: "Shortly after 22.08hrs on Tuesday, 20 December, a 30-year-old man was arrested on suspicion of causing criminal damage after a small fire was seen near the Buckingham Palace gates.
"The man has been taken into custody. The fire has been extinguished."
We'll be bringing you the very latest updates, pictures and video on this breaking news story.
Get all the big headlines, pictures, analysis, opinion and video on the stories that matter to you by following The Mirror every time you see our name.
Follow The Mirror on Google News - CLICK HERE and click the star
Follow The Mirror on Apple News - CLICK HERE available on Apple devices
Follow The Mirror on Flipboard - CLICK HERE and click follow
You can sign up for Twitter alerts for breaking news here @MirrorBreaking_ and follow us @DailyMirror, for all the latest updates.
Keep up-to-date with your must-see news, features, videos and pictures throughout the day by following us on Facebook at facebook.com/dailymirror
See all our social accounts you can follow here: mirror.co.uk/social
