Bodies of dolphins found mutilated with gunshot wounds, cuts and missing jaws has launched an investigation by officials into the attacks covering the northern Gulf of Mexico.

The National Oceanic and Atmospheric Administration has issued a 'heads up' for officials to be on the alert for the barbaric attacks in waters spanning Louisiana, Mississippi and Alabama.

'We think there's someone or some group on a rampage,' Moby Solangi, executive director of Institute for Marine Mammal Studies told the Sun Herald.  'They not only kill them but also mutilate them.'

To one carcass found with its tail cut off in Louisiana, Mr Solangi said: 'Animals don't eat each other's tails off.'

The resulting scene has speckled parts of the Gulf since earlier this year with bodies, though in recent months the IMMS says they’ve increased.