French authorities are searching five sites run by dairy giant Lactalis as part of an investigation into the botched mass recall of baby milk products after a salmonella scare.

The Paris prosecutor’s office said sites being searched on Wednesday include Lactalis headquarters in Laval, in western France, and the factory in Craon, where salmonella bacteria was found last year. The factory has been shut.

Government fraud and health authorities are investigating the handling of the scare and a subsequent mass recall.

Recalled baby milk products remained available in French hospitals, pharmacies and supermarkets weeks after they were ordered pulled from shelves.

Lactalis said the recall affected more than 12 million products in 83 countries.

French authorities said more than 30 babies fell ill after consuming the products, though all have since recovered.