BERLIN -- Money-hating pranksters? Anti globalization activists protesting the root of all evil? Careless chemists?
Theories are plentiful. Clues are few. Just some badly battered banknotes and traces of acid.
But one thing is certain -- the mighty euro is crumbling, at least in Germany.
Police and bank officials said yesterday that more than a thousand banknotes of varying denominations have disintegrated in people's hands, wallets, or pockets in recent weeks, apparently after being accidentally contaminated -- or deliberately doused -- with an acidic powder or spray.
"It's a phenomenon," said Stefan Yongsing-Yue, spokesman for the Berlin police, one of two German departments investigating the corroding currency. "A mystery."
The first flaking euro bills surfaced during the summer, but police shrugged them off as flukes. But now criminal investigators in the German capital and the state of Rhineland-Paltinate have mounted full bore investigations into the matter as hundreds of fragmenting bills have turned up in banks and cashier's tills across the country. Banking authorities in other countries are also looking into the decomposition of the continent's common currency, according to German media accounts, although the so-called broken notes have only been confirmed in Germany.
Police believe that the affected money has been contaminated by sulfuric acid, a corrosive widely used in the chemical industry.
"But we don't know how it was put on the bills," said Yongsing-Yue.
No group or individual has claimed responsibility for the bizarre chemical assault on money, if that's what it is. The damage resembles burn spots and some bills have disintegrated almost entirely, according to police and banking officials.
"Who Wants To Destroy Our Money?" the newspaper Bild demanded in a front-page headline in yesterday's edition.
Police are investigating whether the bills might have been doused with sulfuric acid during transport or processing, but also are looking into whether the destruction is the work of jokers or activists trying to make a statement. In Germany, destruction of currency is classified as vandalism, not a major crime like counterfeiting.
Media speculation ran the gamut from an accident by a careless chemist to some sort of anti capitalist cabal.
"Maybe a racketeer is behind all this, someone who wants to prove to us he can destroy the euro," said a European Central Bank official quoted by Bild.
People stuck with the corroding bills aren't necessarily losers -- the German Bundesbank is replacing notes still recognizable as money.
Annika Mueller de Vries , a spokeswoman for the Bundesbank, said the bank does not believe the disintegration of the bills is the result of a production problem or deficiency in the paper. She confirmed that at least 1,500 euro bills have been returned to the bank damaged, some reduced to just a few tatters.
"We are concerned, but 1,500 bills out of 10.5 billion euro bills is not threatening" to the economy, she said, referring to the total number of bills in circulation in the 12 European countries that share the euro as a common currency.
The largest numbers of crumbling currency have been reported in northern Germany. There have been no confirmed instances of suspiciously disintegrating euro bills outside Germany, police said.
The Bundesbank issued photographs of disintegrating bills and an appeal to the public for information. Most of the damaged money has been in the E20 and E50 denominations. One euro is worth roughly $1.27.
Authorities confirmed that the damaged and destroyed were legitimate euros, printed in Germany, and came from a variety of serial lots and printing dates, which seemed to reduce the possibility of a production problem.
"We still haven't been able to determine if this was an unintentional chemical spill or whether it was a conscious manipulation," a Bundesbank official told Bild.
Petra Krischok of the Globe's Berlin bureau contributed to this report.