In May of this year my wife and I were part of a tour group. On our first subway train trip in Paris, several young girls, 10-12 years old or so, boarded 2 adjacent cars. The locals knew they were pickpockets and told one of our group members, who failed to communicate the alert.
My wife was carrying a shoulder bag, and she had the bag in front, to keep a hand and an eye on it. I recall one of the girls standing near my wife. I did not watch the girl though. The girls got off the train after a couple of stops.
After we got off the subway and were walking down a street with our group, my wife discovered her bag had all the pockets unzipped and that her wallet was gone, which contained our credit cards. Being we were with a large group, it took us a couple of hours to get back to the hotel and call in the theft.
Fortunately, my wife had recorded all the credit card data and emailed it to herself. Using that email, she could give accurate information to the credit card companies. In the 2-3 hours it took us to get this done, the thieves had racked up several thousand dollars in charges. The children appear to be working for adults and have quite a racket going.
Despite this, Barcelona was the absolute worst place on our trip for pickpockets. There were at four pickpocket attempts on our group of about 40, and over a 2 day period, that was about a 5% chance of a pickpocket attempt per day.
A relative of ours and a friend were hit too in Barcelona. 2 guys came up and said they were with the police and wanted to see their passports. That required them to dig out their wallets, where people usually keep their passports. The guys snatched one of the wallets and ran. The wallet had about 800 Euros in it.
Be careful over there. Europe is packed with thieves.