Volkswagen shares plunged more than 20 percent on Monday, their biggest one-day fall, after the German carmaker admitted it had rigged emissions tests in the United States, and U.S. authorities said they would widen their probe to other manufacturers. Germany, alarmed at the potential damage the scandal could inflict on its world-beating car industry, urged Volkswagen to fully clear up the matter and said it would investigate whether emissions data had also been falsified in Europe. The U.S. Environmental Protection Agency (EPA) said on Friday Europe’s biggest carmaker had used software for diesel VW and Audi branded cars that deceived regulators measuring toxic emissions and could face penalties of up to $18 billion.
