A monstrous-looking sea creature that experts are unable to identify has washed up on a tourist beach in Mexico.

The strange 4-meter (13-foot-long) beast was found by beach-goers on Bonfil Beach, in the city of Acapulco, in the south-west Mexican state of Guerrero.

Stunned spectators gathered around and took photos, which they shared on social media, speculating about the possible species of the creature.

Mysterious: An unidentified sea animal washed up on the popular Bonfil Beach in Acapulco, Mexico. The floating body was brought to shore by strong currents that have been affecting that part of the Mexican coast

The floating body was brought to the shore by strong currents that have been affecting that particular part of the Mexican coast.

Although the coordinator of the Civil Guard and Fire Brigade, Rosa Camacho, believes the animal had not been dead for a long time, it still seemed to have rapidly started to decay.

'We have no idea what type of animal this is, but I do know that it does not smell bad or have a fetid aroma,' Camacho stated.

'It is four meters long and was found on Bonfil Beach.'

The many photos of the strange creature have been seen and shared online thousands of times and have provoked a debate about what kind of animal it is.

Some have suggested that the creature might be a type of giant squid and others a whale.