Berlin (CNN) -- The outbreak of E. coli in Germany has killed several more people and sickened hundreds, authorities said Tuesday.
News reports citing local authorities reported 16 deaths linked to E. coli in some raw vegetables. CNN has confirmed at least 12 deaths.
As more people have died, the outbreak has shown itself to be spreading geographically as well. No longer contained in northern Germany, the outbreak has killed at least two people in the western part of the country.
One of the 16 deaths was in Sweden. A woman died after visiting Germany, the Swedish Ministry for Health and Social Affairs said.
The Robert Koch Institute, Germany's federal unit responsible for disease control and prevention, said 373 people have been confirmed sickened. But figures coming in from local authorities and hospitals made clear many more people are believed to be infected.
"Here in Hamburg we're pretty much at the epicenter," Jorg Debatin, medical director of the Hamburg Medical Center, told CNN. His hospital has 600 to 700 infected patients, Debatin said. About 20% to 30% of them develop hemolytic-uremic syndrome, or HUS, "a very severe complication," he said.
The hospital is especially concerned about 85 patients -- 20 children and 65 adults -- who may go into renal failure and develop neurologic symptoms, he said.
Sweden's health ministry said there have been 39 confirmed cases of people sickened by E. coli in Sweden, 16 of which are being investigated for complications caused by HUS. All 39 patients recently visited 39 Germany.
No contaminated vegetables have been reported in Sweden, the ministry said.
While authorities in Germany worked to contain and respond to the outbreak, the specific cause remained unclear.
The European Food Safety Alert Network said EHEC, or enterohemorrhagic Escherichia coli, a strain of E. coli that causes hemorrhage in the intestines, was found in organic cucumbers originating from Spain, packaged in Germany, and distributed to countries including Austria, the Czech Republic, Denmark, Germany, Hungary, Luxembourg and Spain.
But the source has not yet been pinpointed, authorities said.
Hans-Joachim Breetz, executive director of Hamburg's Institute for Sanitation and Environment, said it can take days or weeks to find a source of infection.
In the meantime, "the warning remains not to eat raw cucumbers, leaf lettuce or tomatoes," said Cornelia Pruefer-Storcks,
Hamburg's top official for health and consumer protection.
European Union spokeswoman Pia Ahrenkilde-Hansen told CNN that German authorities were examining cucumber batches from the Spanish cities of Almeria and Malaga as potential sources of infection. She also said a shipment originating in Denmark or the Netherlands is being checked.
The questions surrounding produce from Spain have "paralyzed" vegetable exports, a spokeswoman for Fepex, the Spanish export producers group for vegetables and fruits, said Tuesday.
The industry in Spain expects weekly losses of about 200 million euros ($288 million), Fepex officials said.
Fepex President Jorge Brotons and Director General Jose Maria Pozancos called on Spanish Prime Minister Jose Luis Rodriguez Zapatero to step in, the spokeswoman said. The Fepex officials argue that German authorities have accused the Spanish cucumber of being the source of the outbreak, without proof.
Spanish Health Minister Leire Pajin discussed the outbreak on Twitter. "In the absence of proof. we're not ruling out using all necessary measures to make sure there's compensation for the (economic) damage," she wrote. "From the first day, the government launched a diplomatic offensive to prevent the linking of this health crisis with our products."
Germany is the top purchaser of Spain's produce, according to Fepex. In 2010, Spain exported 9.4 million tons of produce; a quarter of that went to Germany, Fepex said.
A Spanish health ministry spokesman told CNN that Spanish authorities are investigating the outbreak. Initial results that could cite a potential casue are expected by Thursday, or possibly as early as Wednesday, the spokesman said.
Spanish authorities are sharing their investigative results with German and European Union authorities, the spokesman added.
The Spanish Agency for Food Safety and Nutrition said two Spanish companies producing cucumbers may be involved in the outbreak. The agency was awaiting further results from Germany's investigation.
The Robert Koch Institute said Germany's Federal Institute for Risk Assessment "advised against eating raw tomatoes, cucumbers and lettuces to prevent further cases."
CNN's Frederik Pleitgen and Eileen Hsieh contributed to this report.