Mystery surrounds how the decomposing carcass of a sea creature came to be in a suitcase near a Romney Marsh car park.

An unsuspecting dog walker made the grim discovery in St Mary's Bay just after dawn this morning.

Chris Perkins walks his dog along the same beach route every day, and said he had not spotted the holdall 24 hours earlier on Monday.

Warning - graphic image below

The Dymchurch resident said he found the animal on the sea wall near the car park at around 5am: "It was very weird.

"The suitcase was already open."

He said the object caught his eye: "As soon as I got up to that end of the car park, I saw something stuck out the grass.

"Someone had put it on top of the sea wall near the pathway, and lots of people walk that way.

"It had been dead a long time."

He also said the hot weather made an impact on the smell: "It was really awful.

"I'm pretty sure it's a porpoise because it's got a dorsal fin."

Authorities dealing with the matter found it difficult at first to identify exactly what type of marine life they were dealing with.

A spokesman for the Maritime and Coastguard Agency said: "A dead marine mammal has been found in a suitcase on St Mary’s Bay in Kent.

"Dungeness Coastguard Rescue Team was sent early this morning to check and secure the scene after the find was reported to HM Coastguard shortly after 7.30am this morning.

"It has also been reported to the Maritime and Coastguard Agency’s Receiver of Wreck who deals with dead cetaceans such as porpoises on the beaches of the UK as they are classed as Royal Fish."

Alison Kentuck, Receiver of Wreck, said: "This is an unusual one. We have dealt with cetaceans stranded all around the UK, sometimes in strange places, but I have never seen one packed in a suitcase before.

"It is quite decomposed and, at first sight, it seemed that it might be a small seal rather than a porpoise which means it wouldn’t come under our remit.

"However, colleagues at the Cetacean Strandings Investigation Programme have identified it as a porpoise, but the state of decomposition is such they would not want to collect the animal for further study so the local council has been asked to dispose of it."

A spokesman for Folkestone and Hythe District council (FHDC) said: "We were made aware of this this morning.

"We visited the beach earlier today but, from the location we had been given, we could not find the suitcase or the porpoise.

"We have now been given more accurate information and are currently re-visiting the beach where we will hopefully find the dead porpoise and remove it."

It is not known how the animal came to be in the case.

Concerned residents speculated on social media about whether foul play was involved, or if someone had been trying to conceal the carcass from others to avoid distress.

Others also reported seeing a person with a suitcase near the area yesterday afternoon.

The RSPCA confirmed it had not been called about the incident.

Police also confirmed they received a report, but passed it on to FHDC.

The UK Cetacean Strandings Investigation Programme advises that if you find a stranded marine animal to contact either the RSPCA on 0300 1234999 or British Divers Marine Life Rescue on 01825 765546.