Shots fired outside UK Parliament

There are reports of shots being fired outside the Houses of Parliament and the Palace of Westminster is reportedly in lockdown.

Politicians and journalists have tweeted about hearing loud crashes outside the buildings, as witnesses said they saw people being treated for injuries.

Witnesses have reported seeing a man with a knife within the palace grounds.

A police officer has also told the BBC's political editor Laura Kuenssberg that someone has been shot outside Portcullis House.