The number of confirmed E.coli cases has risen to 11 with at least another eight persons suspected of having the intestinal infection in Denmark, according to Denmark's National Serum Institute on Sunday.

Five of the confirmed cases show symptoms of kidney failure which marks an advanced stage of the sickness, the institute said.

Danish cucumbers are suspected of helping spread the E. coli bacteria believed to be causing a deadly outbreak of intestinal infection in Denmark and Germany, local media reported Sunday.

The Danish cucumbers were mixed in Germany with cucumbers originating in the Netherlands, making it difficult to determine if Danish cucumbers are in fact contaminated.

Denmark's Veterinary and Food Administration (DVFA) had earlier said the suspicion against Danish cucumber was "vague", but advised Danish consumers not to eat raw tomatoes, lettuces and cucumbers from Germany, and cucumber from Spain.

It is now checking Danish cucumbers for traces of E. coli with results expected on Tuesday.

Some Danish retailers have now removed these products from their supermarket shelves. And the Danish branch of fast-food chain McDonald's announced Saturday that it was dropping fresh cucumbers from its menu until further notice.

The infection, which is food-borne, can be caused by eating raw or uncooked foods such as vegetables contaminated with the E. coli bacteria.

Symptoms of infection include mild fever, bloody diarrhea and vomiting, and can last five to seven days. It can prove fatal in the very young, sick, or elderly.