PARIS: French Defense Minister Jean-Yves Le Drian said Sunday that a chemical or biological attack “was among the risks” in the wake of the Paris attacks but that all possible precautions to avoid such a scenario had been taken.

He said French authorities were not ruling anything out in the wake of the Paris attacks even though it was “very complicated” for anyone to use chemical weapons.

“All the precautions have been taken to avoid this kind of risk,” Le Drian told Europe 1 radio.

Prime Minister Manuel Valls had on Thursday said that an attack using chemical or biological weapons was possible.

“We must not rule anything out... There is also the risk from chemical or biological weapons,” Valls said in the aftermath of the shootings and suicide bombings on November 13 that killed 130 people.

Police are investigating the recent theft of medical protective clothing from a hospital in Paris. The motive for the theft is unclear but it comes amid heightened fears in France over the risk of biological or chemical terrorism.

Police have issued a new appeal to identify the third man involved in the attacks at the national stadium on Nov. 13. Police on Sunday posted a photo of the man on Twitter, appealing to the public for information that would help identify him.

The man was among three people who died in the attacks outside the stadium.

Meanwhile, Iraqi and US intelligence officials say Daesh is aggressively pursuing development of chemical weapons, setting up a branch dedicated to research and experiments with the help of scientists from Iraq, Syria and elsewhere in the region.