VIENNA, Austria (AFP) -- A supplier of baby food jars in Austria is recalling a line after discovering that rat poison may have been introduced through tampering.

The HiPP brand said it was recalling its "entire line of baby food jars sold at SPAR Austria" as "it cannot be ruled out that a hazardous substance was introduced into the 'HiPP Carrot/Potato 190 grams' product through tampering, and consumption could be fatal."

Austria's agency for food protection said police were investigating and that the rat poison may have been introduced as part of an extortion scheme.

Customers were asked not to consume the product, which can be identified by a white label with a red circle on the bottom of the jar, and instead return it to the store of purchase.

Police in the eastern Burgenland region have put out a call for witnesses, according to the statement.

The national food agency said that so far the contaminated jars had been found at a SPAR store in the east of the country and in two Tesco stores in neighboring Czech Republic.