Buckingham Palace is on lockdown after a man with a knife was arrested for attacking police officers.
Two male police officers were treated at the scene for minor arm injuries and were not taken to hospital, the Metropolitan Police said.
"During the course of detaining him, two male police officers suffered minor injuries to their arm," a Metropolitan police statement said.
"The London Ambulance Service were called and they were treated at the scene. They have not been taken to hospital.”
"No others persons have been reported injured. Officers remain on scene and enquiries are ongoing."
A Buckingham Palace spokeswoman declined the opportunity to comment on security issues.
Eyewitness Nicole Kyle, 25, said she was walking toward The Mall and St James’s Park when police began to rush toward the palace.
“As we got further down The Mall we saw armed police outside a police van, at which point we were able to walk closer to the palace still, where we were eventually stopped by a cordon,” she told the Press Association.
“All we were told was that there’s been an incident. A few minutes later police came by to have us clear the area and move further away from the palace. We then saw that police had expanded the cordon.”
She added: “It looks like the cordon is continuing to expand.”
Another witness, Leonardi Paoli, wrote on Twitter: "Buckingham Palace in lockdown. Man with a sword attacked an officer."
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