Soldiers on exercise in Kenya. The image, by Sergeant Dek Traylor, is among the section winners in the UK Army Photographic Competition 2018. (Photo by Sergeant Dek Traylor/PA Wire Press Association)

Revellers in Newcastle, England on the last Friday before Christmas, December 20, 2019. Black Eye Friday festive mayhem hit the nation; Christmas celebrations kicked off with a bang across the country as revellers flocked to pubs and clubs for the biggest night of the year. (Photo by Scott Heppell/PA Images via Getty Images)

Planes land in fog at Heathrow Airport, west London, as heavy fog covers a many parts of the south east, on April 1, 2014. (Photo by Steve Parsons/PA Wire)

Handout photo dated March 20, 2015 issued by Chester Zoo of lemurs looking at the eclipse over Chester Zoo. (Photo by Steve Rawlins/PA Wire/Chester Zoo)

The sun rises beside St Mary's Lighthouse in Whitley Bay, Tyne and Wear, as the unseasonably cool weather continues on Thursday, April 28, 2016. (Photo by Owen Humphreys/PA Wire)

Let the fun begin. Revellers carry their belongings as they arrive at Worthy Farm in Somerset for the Glastonbury Festival, Britain, June 22, 2016. Around 180,000 are expected to attend. (Photo by Ben Birchall/PA Wire)

Undated David Yarrow handout photo of a gorilla as the self-taught wildlife photographer promotes his book, Encounter. (Photo by David Yarrow/Clearview/PA Wire)

Members of the Royal Navy respond to a simulated fire in a Vanguard-class submarine control room training facility at Clyde naval base in Faslane, Scotland on January 21, 2016. (Photo by Photograph: Danny Lawson/PA Wire)