The dolphin was originally part of a small group swimming off the Mexican coast but the others managed to get away, leaving it at the mercy of a whole pod of whales.

Dramatic: This killer whale was pictured attacking a bottlenose dolphin off the Mexican coast

Astonishing: These photographs record the final act of a chase that lasted two hours

Photographer Christopher Swann, who captured the extraordinary scene, said: ‘The killer whales tore round at full speed for two hours.

‘We never knew where to look because they erupted out of the water in one place, disappeared in a thrashing of foam and reappeared in a totally new location.

‘On one occasion the killer whale burst out of the water directly in front of us, and about six or seven metres ahead.

‘He was about four metres in the air and heading right at us – I thought he was going to land on the boat but it turned mid-air and clattered into the sea beside us.’

Fortunate: Photographer Christopher Swann captured the extraordinary scene

Hunting: The killer whales raced around after the dolphin at full speed for two hours

The father-of-one, who has been whale watching for more than two decades, said the killer whale in the photograph appeared to do most of the chasing.

Mr Swann added: ‘The terror and fight for life of the dolphin was palpable. One felt one could feel the adrenalin in his veins and his pulsing heart as he raced for his life.

‘[He went] back and forth but [was] always met by another whale blocking the way. Sometimes, three or four times, the whales would knock the dolphin out of the water – once with their tail.

Gruesome: As darkness fell, the whales had the dolphin on the surface and it was all over

‘Incredible when you consider that this was a large healthy dolphin. It is staggering how the whales treated it like a plaything.

‘I had the feeling – maybe wrongly of course – the last hour was unnecessary as far as the whales were concerned and that they were just playing with it and then finally, just as darkness fell, they had it on the surface in their midst and it was all over.’