Hundreds of police officers have closed in on Extinction Rebellion protesters in central London as demonstrations entered a fifth day.

Officers surrounded a pink boat in Oxford Circus as actress Dame Emma Thompson told activists her generation had "failed young people".

More than 570 people have been arrested at protests this week in Oxford Circus, Parliament Square and Waterloo Bridge

Dame Emma joined the protests after flying from Los Angeles on Thursday.

She said: "We are here in this little island of sanity and it makes me so happy to be able to join you all and to add my voice to the young people here who have inspired a whole new movement."

Police wearing jackets saying "protester removal team" have begun carrying and leading activists away from the protest in Oxford Circus.

One woman was carried out the cordons by four officers while