The euro dropped against the yen and reached a two-year low against the dollar after a 12th night of rioting in France.

Concern that the social disorder will dampen growth and deter investment in euro-denominated assets also pushed the European currency lower versus 11 other major counterparts. It extended losses against the dollar earlier after sliding past last year’s low, a level where traders had pre-set orders to sell the euro.

“The riots in France will have impacted confidence over Europe, and we’re also seeing key technical levels being broken, pushing the euro lower,” a currency strategist at ABN Amro Holding in London, Paul Mackel, said.

Against the yen, the euro slid to 138.17 yen at 5 p.m. in New York, from 138.92 late yesterday, according to electronic foreign-exchange dealing system EBS. The euro has fallen for four straight days against the yen after reaching an 11-month high of 141.17 on November 3.

The euro fell to $1.1780 from $1.1805 against the dollar after earlier trading as low as $1.1710, the weakest since November 13, 2003. The currency’s drop accelerated in the past two days because traders placed automatic sell orders to limit losses as their bets went the wrong way. The euro’s low for 2004 was $1.1760.

“If people are selling the euro on a technical basis and you get any kind of negative news, it just exacerbates the situation,” said Ryan Schiff, global head of foreign exchange at Fimat Group in Chicago, whose company trades about $2 billion in currencies daily.

Some traders who are betting the European Central Bank will keep interest rates on hold while the Federal Reserve keeps raising its benchmark rate may be using the rioting as an excuse to sell the euro. European finance ministers urged the ECB on Monday to refrain from raising interest rates.

“Yesterday was the opening of the hunting season on the euro,” a currency strategist at Dresdner Kleinwort Wasserstein in Frankfurt, Andreas Hahner, said. “People are tying to test how far it’s going to fall.”