A photograph showing the exact moment a pack of grey reef sharks catch and devour a parrotfish sees Briton Richard Barnden named Underwater Photographer of the Year 2019.
The picture, The Gauntlet, was taken late at night on the reefs of French Polynesia in the centre of the Pacific Ocean.
"As I descended, hundreds of sharks covered the bottom. This unlucky parrotfish flinched - and that tiny movement alerted the swarm of sharks," said Barnden.
"The mayhem hurtled straight towards me and I instinctively pressed the shutter, moments later all that remained was a rain of parrotfish scales in the darkness - and this photo on my camera."
Alexander Mustard, who chaired the panel of judges, said; "Photography is about preserving moments - and what an unforgettable instant this is.
"Using a wide-angle lens, the photographer takes us into the full drama of the hunt, as a melee of grey reef sharks rise like a breaking wave to tear apart their prey, truly revealing the ocean's wilder side."
Eduardo Acevedo, from Tenerife, was named Marine Conservation Photographer of the Year 2019 for his photo showing a loggerhead turtle entangled in a discarded plastic fishing net.
Korean Taeyup Kim was named Up & Coming Underwater Photographer of the Year 2019 for a technically challenging image half in and half out of the water, which shows healthy corals growing in front of a resort in French Polynesia.
"This photo was physically tough to shoot, holding the heavy camera exactly in this position while floating in the water," said Kim.
The title of Most Promising British Underwater Photographer 2019 goes to Malcolm Nimmo, from Plymouth.
His image, of a compass jellyfish, was taken while snorkelling off the Scilly Islands.
"Maintaining both the surface features and subject illumination requires high strobe power settings and hence careful strobe positioning," said Nimmo.
"Hopefully this image highlights the beautiful marine environments we are lucky to have around the UK."
The competition had 13 categories, testing photographers with themes such as Macro, Wide Angle, Behaviour and Wreck Photography, as well as four categories for photos taken in British waters.