PARIS, Dec. 26 (Xinhua) -- French prosecutors have opened an investigation into the country's dairy giant Lactalis' salmonella contamination, local media reported on Tuesday.

Health division of Paris prosecutor office launched a preliminary probe for "involuntary injuries", "putting in danger the life of others" and "non-performance of recall procedure", said local broadcaster Europe1.

On Dec. 11, the country's consumer protection agency, DGCCRF, decided to halt the sale of several baby formula milk and baby food products made by Lactalis, and also ordered an international recall of all these products after the discovery of salmonella bacteria.

Following 20 cases of salmonella infection of infants in France, the company, one of the world's leading dairy producers, recalled nearly 7,000 tonnes of packets produced by a contaminated factory in Craon, northwest France.

The salmonella agona bacteria is dangerous for very young and elderly, and provokes severe diarrhoea, stomach cramps and vomiting.