“Anywhere in the country, as long as there is a food store, there will be someone sitting outside it begging,” he added. That is partly because, as he put it, “poor people have noticed that they, too, can move around Europe to try to find a better future.”

Poverty in Romania makes that country a significant point of origin for such migrants, especially for Roma people, also known as Gypsies, many of whom also face prejudice; according to the European Union’s statistics office, Eurostat, Romania has one of the lowest wealth levels in the entire bloc of countries.

In Sweden, the issue has helped fuel the rise of a right-wing, populist, anti-immigration party, the Sweden Democrats, which won 13 percent of the vote in last year’s national elections. There have been similar political reactions in Denmark, France and Britain. In the latter case, concerns about an influx of workers from Southern and Eastern Europe featured prominently in a debate over whether Britain should quit the European Union.

“It is the biggest change in decades,” said Andreas Johansson Heino, publishing director of Timbro, a research institute, referring to the rise of the Sweden Democrats. “In Sweden, the lack of an anti-immigrant party was part of Swedish identity. We thought that here, we don’t have such populist parties.”

Begging is not illegal in Sweden, but the Sweden Democrats want to criminalize it — at least in what the party calls its “organized” form. The police here say there some 4,000 beggars in Sweden, of which 1,000 to 1,500 are in Stockholm.

Linda Staaf, head of the intelligence division at the Swedish police department of national operations, said attacks against the Roma have increased, and opinion among Swedes is polarized between those hostile to begging, and those who see beggars as people in need of help.