Greenpeace activists scale Nelson's Column and deface statues across London in air pollution protest

Police have made multiple arrests as dust and gas masks appeared across on statues across the capital

Activists have scaled a number of landmarks across London in a mass protest demanding action over the city's levels of air pollution.

Greenpeace posted images across social media showing dust masks and mock gas masks on statues of Oliver Cromwell, Queen Victoria, Eros, Winston Churchill and Horatio Nelson.

Four protesters were able to get past security at the Houses of Parliament and scaled the statue of Cromwell within the grounds of the Palace of Westminster.

Police were called at 6.25am as a man and a woman, in climbing gear and hard hats bearing the Greenpeace logo, put a face mask over the statue.

Eight people were arrested on the grounds outside the Houses of Parliament in an security breach that will prove embarrassing to authorities.

Greenpeace posted images to social media showing the view from the top of Nelson's Column (Greenpeace)

Greenpeace released images showing more protesters climbing the 52m-tall Nelson's Column in Trafalgar Square, adding it was "quite a view from the top".

The organisation said it had targeted a total of 17 statues across the city, also including those of Thierry Henry outside Arsenal's football stadium and Sherlock Holmes outside Baker Street Tube station.

Campaigner Areeba Hamid said the protest was timed ahead of the upcoming London mayoral elections:

"Monitoring shows that, if these statutes were real people, many of them would often be breathing dangerous, illegal air.

"That's why we've given them face masks. Of course many millions of Londoners, including kids, are breathing that same air. Kitting everyone out with face masks is not the solution; instead we need to see real political action from the new mayor.

"We need a clean air zone covering a large part of the city. Whoever wins the election has to stop the talk and start the action."

The protest is meant to pressure London mayoral candidates to draw attention to air pollution during London's mayoral election.