If asked "Do you speak English?" while visiting Paris, take a tip from the locals and just say no.
That's one of the pieces of advice now being doled out by tourist officials as the French capital fights a rise in crime targetting foreigners through stepped up security and a publicity campaign to make visitors more aware of the dangers.
Tricksters, cheats and pickpockets abound along the golden strip running along the banks of the Seine from the Eiffel Tower to the famed Notre Dame Cathedral, with landmarks such as the Louvre museum along the way.
A common ploy employed by hustlers is to accost visitors with the line "Do you speak English?" and then get them to sign a petition to support a bogus organisation working for the handicapped or orphans -- and finally demand a donation.
City authorities, who have made free guidebooks available in several languages including English, Russian, Chinese, Japanese, Korean and Spanish, are clear about what to do.
"In such situations, the advice of the Paris chief of police is to be careful, and walk away," the English version of the guide states.
"In fact, the petitioners may tempt you to part with your money. This will never be passed on to charitable organisations, but rather fuel illegal organisations and underground networks. Whilst they divert your attention, an accomplice may be going through your handbag or your pockets."
Paris, which attracted 29 million visitors last year, has deployed about 200 police daily since April at the main tourist landmarks along the Seine as well as the Montmartre area and on public transport in a bid to buck this trend.
Many of the policemen are in plainclothes and on bicycles.
Sonu Singh, an immigrant from India who sells bottled water in the courtyard of the Louvre, said he witnessed "all kinds of nonsense on a daily basis".
"They are a scourge," he said. "They approach people with fake gold rings and ask 'did you drop it?' Then they demand five or 10 euros saying 'Now you have got a gold ring.'"
"It's because of them that people like me are also hauled up by the police. But the police are good and once they realise we're not doing anything dodgy, they let us go," Singh said.
Police say there are rich pickings. An official in the capital's chic seventh arrondissement, where the Eiffel Tower is located, said a single sting yielded 10,000 euros ($13,000).
-- 'These pickpockets are very professional' --
"That's their job. They steal all day long. These pickpocketing teams are very very professional," said Damien Vallot, a police superintendent in the district.
"This phenomenon has grown with the explosion of visitors from China and the Middle East," he said. "They pay the entrance, look like tourists and mingle and buy food and even use taxis to make a getaway."
Concern has grown both in China and France in recent months over the increasing number of thefts and attacks targeting Chinese tourists, many of whom carry huge amounts of cash. In March, robbers targeted a group of 23 Chinese tourists in a restaurant shortly after they arrived in Paris.
One scam is a game in which three discs, only one of which has a white circle on the obverse side, are shuffled and placed along a line.
The punter stands to double a bet of 50 euros by correctly picking the disc with the white circle in the swindle that police say is chiefly staged by Latin Americans.
A swarthy middle-aged man running one such betting game opposite the Eiffel Tower, yells in English, "Attention, I take all money -- pound, dollar, euro." Then an elegantly dressed woman -- an accomplice it later emerges -- bets several times and makes a huge amount of money before walking off.
That prompts Kathy Reynolds, a student from Virginia on her first visit to Europe, to bet 50 euros, which she promptly waves goodbye to.
After that she sees the female accomplice come back and start betting again to lure other gullible onlookers and realises she's been had.
"I wanted to make a fast buck. It looked really easy but he switched it at the last minute," Reynolds said of the conman, who dealt out the discs at lightning speed like a seasoned croupier.
Her companion, who identified herself as Krista, said: "London's a lot safer to move around. Here you feel people are targeting you all the time."
Tom Porter, a 43-year-old New Zealander, agreed.
"We were warned about Rome but we saw nothing and nothing happened. Here you are accosted everywhere, it's in your face."
A leading association grouping French luxury brands recently asked authorities to deal with the climate of insecurity, warning that it could keep cash-flush tourists away.
"As Asian tourism in particular is developing, we wouldn't want it to divert towards Milan or London because it is too risky in Paris," said Elisabeth Ponsolle des Portes of the Comite Colbert association.
Workers at the Louvre museum went on strike in April to protest increasingly aggressive pickpockets, forcing its closure for one day. More police have been deployed there since.
But the criticism is unfair, some argue, underlining that all tourist destinations have their fair share of crooks.
Dolon Roy from New Delhi said the Taj Mahal city of Agra was infinitely worse.
"There you feel the touts and frauds scuttling like cockroaches all over," she said. "That's not the case in Paris."