The possibility of a mass casualty strike on a city in the west or elsewhere by Islamic militants using some kind of biological or chemical agent is a nightmare scenario. French PM Manuel Valls warns of possibility of chemical or biological attack by Isis, but even capable extremists have amassed little that constitutes a real threat 
 
 Manuel Valls, the French prime minister, has said the associates of extremists who targeted France last week could use chemical and biological weapons. U.S. intelligence officials don't believe IS has the capability to develop sophisticated weapons like nerve gas that are most suited for a terrorist attack on a civilian target. So far the group has used mustard gas on the battlefield in Iraq and Syria. Iraqi authorities clearly fear the use could be expanded.
– French PM Manuel Valls issued a new warning in front of the lower house of France's Parliament Thursday, nearly a week after the Paris terror attacks. "Terrorism hit France not because of what it is doing in Iraq and Syria … but for what it is. We know that there could also be a risk of chemical or biological weapons," he said, per the AP. "The macabre imagination of the masterminds is limitless," he added, per the Jerusalem Post. Hakim al-Zamili, the head of the Iraqi parliament's security and defense committee, concurs, telling the AP that "[ISIS] is working very seriously to reach production of chemical weapons, particularly nerve gas. That would threaten not just Iraq but the whole world." Iraqi intelligence officers say ISIS has a dedicated arm going after chemical weapons, and al-Zamili notes ISIS has plenty of chemical experts from Iraq—including some of Saddam's ex-hired hands—and abroad and that research labs are now in "secured locations" in Syria. So far, the only evidence of what ISIS has in its chemical arsenal has been mustard gas used in Syria and against Iraqi Kurds—and an EU official tells the AP that was in small amounts and of subpar quality. The US doesn't think the militants can make more sophisticated weapons such as nerve gas—the Guardian concurs, saying ISIS using any chemical weapons in Europe is "extremely unlikely"—but Iraqi officials don't share that confidence. "[Extremists] now have complete freedom to select locations for their labs and production sites and have a wide range of experts, both civilians and military, to aid them," a senior Iraqi intelligence official tells the AP. It looks like France isn't taking any chances: Per a decree signed the day after the Paris attacks and appearing in the French Official Gazette, France gave the OK to use atropine sulfate, a nerve gas antidote, on the masses ahead of the Paris climate talks set for month's end, per Newsweek.