BRUSSELS, Belgium - Europeans traded blame Monday over the source of a mysterious bacterial outbreak that has killed 14 people and sickened hundreds across the continent and forced Russia to ban imports of some fresh vegetables from Spain and Germany out of fear of contamination.

Austrian authorities sent inspectors to supermarkets to make sure Spanish vegetables suspected of contamination had been taken off shelves. In Italy, the paramilitary Carabinieri has been on the lookout since Saturday for suspected contaminated imports from Spain, the Netherlands, and other European countries.

Pia Ahrenkilde Hansen, a European Union spokeswoman, said that German authorities had identified cucumbers from Almeria and Malaga in Spain as possible sources of contamination, and that a third suspect batch, originating in either the Netherlands or Denmark and traded in Germany, was also under investigation.

In Germany, which has recorded the most infections and all known deaths, officials said they knew that at least some Spanish cucumbers tainted with enterohemorrhagic E. coli, or EHEC, carried the bacteria, though they had been unable to determine the exact source.

An EU official, speaking on condition of anonymity because of standing regulations, said the transport chain was long and the cucumbers from Spain could have been contaminated at any point along the route.

Spain said there was no proof the outbreak was caused by its vegetables.

The World Health Organization urged countries to work together to get to the root of the problem.