Officials from Birmingham City Council, UK, are testing another 30 Cadbury's brands as there is a chance the initial list of salmonella infected brands did not include several others. A week ago the company took over one million chocolate bars off the market after salmonella had been identified in some of them.

Salmonella Montevideo has been identified in some brands. This is a very rare strain.

According to Cadbury's, the chocolate on the shelves now in retail outlets are safe.

The contamination has been due to a leaking pipe at Cadbury's Marlbrook plant, Herefordshire, UK. Apparently, Cadbury's has known about this since last January but said nothing about it until June. The company could face prosecution for keeping the incident quiet. There has been an unusual rise this year of salmonella Montevideo infections in the UK.

Warnings have been issued of potential salmonella contamination in the following brands:

-- 250g Dairy Milk Turkish
-- Dairy Milk Caramel bars
-- Dairy Milk Mint
-- Dairy Milk 8 chunk
-- 1kg Dairy Milk bar
-- Dairy Milk Buttons Easter Egg
-- Freddo bar

A spokesman for Birmingham City Council's food safety team said that as a result of the publicity last week, and in cooperation with the chocolate manufacturers, the Council is independently testing both current product lines and past product lines that have been returned. They said they want to find out whether there is any contamination of current or past stocks.

The mix used to make the brands that were removed was also used to make other brands that were not removed. Up to 30 brands could be affected. The Food Standards Agency said that in view of this it is not possible to exclude the other brands from the possible contaminated list.

Cadbury's says that it has tested literally tens of thousands of items of confectionary and has not identified one single case of salmonella contamination. Product lines are currently being tested at least four times each day, says the company.