E. coli outbreak spreads in Europe (VIDEO)

Authorities in Europe on Monday stepped up efforts to stop the spread of a deadly E. coli outbreak that has killed at least 14 people in Germany. The European Center for Disease Prevention and Control has described the outbreak as “one of the largest worldwide and the largest ever reported in Germany," according to the Globe and Mail.

Russia banned the import of vegetables from Germany and Spain, Austrian authorities are inspecting and removing suspected infected produce, and Italy has put the paramilitary Carabinieri in charge of searching for suspected contaminated imports from Spain, the Netherlands and other countries, the Wall Street Journal reported.

Food safety officials have been trying for more than two weeks to pin down the source of the contamination, which first showed up in Hamburg and has since hit people in Britain, Denmark, Sweden and the Netherlands, according to the Globe and Mail. Hundreds of Europeans have suffered from diarrhea, cramps and other symptoms. Germany, which has seen the widest outbreak and all the known deaths, said Spanish cucumbers could be a source, the New York Times reported.

Pia Ahrenkilde Hansen, a European Union spokeswoman, said German authorities thought that cucumbers from the Spanish cities of Almeira and Malaga were possible sources of contamination and that a third suspect shipment, originating either in the Netherlands or in Denmark and traded in Germany, is also under investigation.

One question was whether the disease could have developed on delivery routes between Spain and Germany, or in storage areas, according to the New York Times. An unnamed official quoted by the Wall Street Journal pointed out that the contamination could have occurred anywhere along the transport route of the cucumbers.

The Spanish environment minister, Rosa Aguilar, said that "it's not true" that the outbreak started in Spain, and said that investigations that are being conducted had to be completed as soon as possible. She said that German authorities "must stop fingering Spain" for the outbreak, the Wall Street Journal said.