A police officer has been stabbed outside Parliament - and a car has been driven into the fence that surrounds Parliament, after hitting people on Westminster Bridge, it appears.
According to the BBC House of Commons Leader David Lidington the assailant has since been shot by armed police. Prime Minister Theresa May was inside Parliament at the time - but is now said to have been evacuated, and is safe. Parliament itself has been suspended.
Reports suggest anything from 3 to 12 people injured on Westminster bridge. One eyewitness just told us he saw at least eight on the ground pic.twitter.com/i3fqzsPPc1
— Nick Martin (@NickMartinSKY) March 22, 2017
This is obviously a breaking news event, so the full story will not be clear for some time. We'll update this post when we know more.