The mayor of Venice has vowed to investigate an alleged restaurant rip-off in which four Japanese tourists claim they were charged €1100 ($1840) for a plate of fried fish, four steaks and a bottle of wine.
Luigi Brugnaro said that if the "disgraceful" episode was proved then the owners of the restaurant near St Mark's Square would be prosecuted.
"We will thoroughly examine this episode and check to see if the complaint was made properly," Brugnaro wrote on his Twitter account.
"If this disgraceful episode is confirmed, we'll do all we can to punish those responsible. We are for justice – always."
The case came to light on Sunday when it emerged that the four Japanese tourists had made a formal complaint after they left Venice and returned to Bologna, where they are studying.
They said they had paid €1100 for a plate of fried fish, four steaks, a bottle of wine and a bottle of mineral water.
It was not clear why they agreed to pay the bill rather than kick up a fuss.
Telephone calls to the restaurant went unanswered yesterday but on Sunday, when asked about the bill, the owner told Italian journalists: "I don't remember having any problems with Japanese customers."
The case has been picked up by an association of local campaigners, called the April 25 Group. "Whoever jeopardises the good name of Venice harms all Venetians," the group said.
It is just the latest report of tourists, often Asians, being brazenly overcharged by restaurants in Venice.
In November, a British tourist wrote a letter of complaint to the mayor after he and his parents were allegedly charged €526 ($880) for lunch in a restaurant, also near St Mark's Square.
Luke Tang, a university lecturer from Birmingham, said he and his 70-year-old parents were shocked to be charged so much for the seafood meal, much of which they had not ordered.
He accused the waiters in the restaurant of taking advantage of the fact that neither he nor his parents spoke any Italian.
In the letter to Brugnaro, he wrote: "I do not expect there will be any refund, but I wanted to draw your attention (to) the behaviour of this business, (which) will ruin the reputation of Venice. It is disgraceful and indeed the shame of Venice."