New documents show that the FDA investigated reports that up to nine infants died after consuming baby formula made by Abbott Nutrition at its Michigan factory.

Nine deaths linked to baby formula were among 128 consumer complaints to the FDA between December 1 last year and March 3 according to a filing obtained by the website e Food Alert.

The Washington Post was the first to report it.

Two of the deaths were connected to a Cronobacter sakazakii outbreak reported by the CDC.

There were instances of Cronobacter sakazakii in the environment of Abbott's factory.

Two deaths mentioned "Salmonella" in the report, while 25 other instances were categorized as "life threatening illness/injury." The infants were only identified by reference numbers.

Most of the babies suffered with multiple symptoms, including a high temperature, vomiting, and blood in their stool, but the symptoms in the 128 cases were mostly the same.

The FDA and the White House took unprecedented measures, including imports from Europe and Australia, because of the outbreak.

Abbott and the FDA agreed to restart production this month.

The FDA told The Washington Post that there were only four complaints that could be included in the case series.

Abbott told The Post there was no correlation between its baby formula and the deaths.

No Abbott formula distributed to consumers tested positive for either Cronobacter sakazakii orSalmonella. The retained product tested by Abbott and the FDA came back negative for both Cronobacter sakazakii andSalmonella. The company told the newspaper that there was no outbreak of the disease.

Insider requested comment from Abbott and the FDA outside normal working hours.