Sausage, the ginger mongrel who became famous for appearing at anti-austerity protests at the height of Greece's debt crisis, has died of a heart attack, the ABC reports.
The stray dog, nicknamed Sausage or "Loukanikos" in Greek, became a media sensation and public darling in 2011 by regularly showing up on the side of demonstrators and yelping at police amid the chaos of teargas and flying petrol bombs.
He was named runner up for Time Magazine's Animal of the Year in 2011, only beaten to the top spot by the army dog that accompanied the US Navy SEAL team which took down Osama Bin Laden.
"He was Greek. Like all stray animals, Loukanikos somehow reflected the restlessness of Greeks who refuse to bow down," Anna Makri, a veterinarian who heads the city's stray animal service, said.
"The doctor's assessment was that he died suddenly, of a heart attack."
Sausage ended up appearing on the front page of most Greek newspapers and wagged his tail on television screens as violent anti-bailout protests raged behind him.
Ms Makri said a Greek animal welfare group took Sausage in about two years ago.
The leftist Avgi newspaper said he had been buried under a tree on a hill in the city centre.
Stray dogs are a common sight in Athens. Most are monitored by city authorities and wear collars and tags with a phone number to call if they are in - or causing - trouble.