By Gerard Couzens PUBLISHED: 07:17 EST, 23 August 2013 | UPDATED: 11:02 EST, 24 August 2013 Spanish police have come under fire for sending divers to inspect a concrete reef in Gibraltan waters who then took underwater pictures of themselves unfurling the Spanish flag. The divers then posted the images on Twitter while Spain's Guardia Civil police released footage of the diving stunt last night. Gibraltar has accused the police of violating 'British sovereignty' by attempting to exercise jurisdiction in its territory.Scroll down for video Incursion: A Spanish police diver hold up the Spanish flag while inspecting one of the concrete blocks dropped by the Gibraltan government off the coast to encourage marine life
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Police divers took pictures of themselves posing with the Spanish flag by the man-made reef and then posted them on Twitter
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Gibraltar Governor Sir Adrian Johns criticised the diving stunt
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Meanwhile chief minister Fabian Picardo is seeking to defuse dispute with Spain by letting its fishermen return to British waters
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It would allow around 59 boats to return to their traditional fishing grounds
Spain wants the reef removed, claiming it prevents @placeholder fishermen from accessing the waters surrounding Gibraltar.