Ly Nhat Thu, a tour guide with many years of experience in taking Vietnamese tourists around the city, says the number of tourists has been on the rise this summer with tourist destinations packed with holiday-goers.
To avoid pickpockets, visitors need to be aware of them first.
"Beware of four-to-five-year-old kids, usually very pretty girls who hold cups and beg for money."
These children often walk alone and are sometimes accompanied by a pregnant woman or a woman with a child.
Vietnamese tourists coming to Rome also need to be wary of "pregnant women," women who only pretend to be pregnant to allay suspicion when they approach someone to pick their pocket.
In terms of modus operandi, the thieves usually operate at metro stations. When a train stops for 30-60 seconds, they board the train to look for prey in crowded carriages. They get off if the carriage is empty or they find it difficult to operate.
Thu has often seen them use their feet or body to block the train doors to make it easy to get on or off.
The pickpockets often target Asian tourists traveling alone or in small groups and western tourists traveling for the first time. They take turn distracting people while others steal their wallet and other items.
Thu recommends that visitors should keep their passport in the hotel safe and just keep a photo of it on their phone in case police officers ask for it.
Backpacks should only be used for unimportant things like water bottles, tissues, scarves, or light coats. Visitors should carry little cash and keep it in an inconspicuous place and make all payment online.
On the metro, people should avoid standing by the door if they do not want to fall victim to robbers and pickpockets. They should be careful about persons behind them, and choose the first or last car, which are often empty.
On buses, they should be even more careful. Visitors should hold their phone and bag with valuables in their hands or sling the bag around their neck.
They should dress modestly and avoid wearing expensive brands and watches.
Italy has been named the destination with the biggest threat of pickpocketing in Europe followed by France in a report by British insurance comparison website Quotezone.
The list was based on the number of mentions of pickpocketing in visitors’ reviews of a country's top five tourist attractions on the world's largest travel review site, Tripadvisor.
Thousands of travelers reported experiencing petty theft while visiting Europe, Quotezone said.