(AFP) Health officials were baffled today by the source of a cholera outbreak which had infected 90 people and killed one, a statement said.

The number of suspected cases in the outbreak in Selangor had risen to 146, according to the statement from the state health officials, quoted by Bernama news agency.

Klang district was the worst hit, with 80 confirmed cases and 118 suspected ones.

Health officials have sent 200 food samples for analysis but none of the results so far have identified the cholera bacteria, according to reports.

Ten water samples had also been taken but test results were not ready yet.

Almost 200 food stalls have been inspected in one area alone and 132 of them have been ordered closed.