Police have arrested a woman who was trying to scale the fence around Queen Elizabeth's Buckingham Palace home in central London, saying the incident is not terrorism-related.
"The woman, believed to be in her 30s, was quickly detained by officers, before she gained access to the palace grounds," police said on Saturday evening.
She was arrested on suspicion of trespass and is being questioned at a central London police station.
"The incident is not being treated as terrorist-related," police said.
Video posted on social media showed the woman being physically restrained by two police officers, in front of stunned tourists.
The woman was wearing jeans and a black top, and was shouting as she was led away to a waiting police car.
The railings around the palace are about 6.4 metres high.
Last year, a 21-year-old man was arrested for climbing a side wall to the palace.
In 2003, Leeds midwife Lindis Percy scaled the palace gates to protest a visit by US President George Bush.
"I was amazed at the ease of it," she claimed.