A video of the attack, which took place earlier this month on a beach in the town of Chalkida, has gone viral on Greek social media, sparking outrage and anger.
A huge crowd of sunbathing tourists can be seen gathered at the water’s edge while the one-metre long fish swims frantically among them.
Several young men try to grab the wriggling fish while others can be seen hurling stones and other objects at the animal.
After a while the swordfish, which some reports said was in fact another species, managed to escape and swam away, pursued by a group of men and more stones.
It was later found dead by officials at the harbour. Although it has not yet undergone an autopsy to find out the cause of death, many in Greece blame the tourists for the creature’s demise.
A petition which demands the bathers involved are prosecuted and fined, as well as the harbourmaster employees who allegedly failed to intervene, has already reached 27,000 signatures.
The petition will be sent to the Greek police and the country’s animal protection authorities.
“It is time to stop the horrible tactics of animal abuse in our country,” the petition states. “We ask for a fine to everyone involved… as well as to the port [officials] that allegedly were there and did not intervene.
“We know, of course, that this is not a protected species, but our voice must be heard so that the unacceptable mob behaviour towards every weak creature finally stops.”
Unconfirmed reports on social media suggest some of the bathers initially feared the swordfish, which was swimming close to the surface with its dorsal fin sticking out of the water, was a shark.
Others said the fish had come in so close to land because it was trying to find a place where it could breed.
In a statement quoted by Greek media outlets, an officer from the Chalkida Port Authority said the harbour staff at the time had not realised the animal had become disorientated and accidentally come in so close to the tourists enjoying the waters.
“A minute after the incident with the bathers, a lifeguard of the harbour found it dead,” the spokesman said.
The body of the swordfish has been transferred to a morgue in Chalkida where it will be examined by vets to determine the cause of death.
Some unconfirmed reports said the video of the incident had been sent to the local prosecutor, who will decide if a crime has been committed.
Swordfish are common throughout the Atlantic, Pacific, Indian and Mediterranean Oceans, but the World Wildlife Fund has warned the species is being caught in the Mediterranean at twice the sustainable rate, and stocks have declined by 88 per cent in biomass terms since the mid 1980s.