France could face the risk of chemical or bacterial warfare in its fight against Islamist militants, French Prime Minister Manuel Valls said on Thursday.
"We must not rule anything out. I say it with all the precautions needed. But we know and bear in mind that there is also a risk of chemical or bacteriological weapons," Valls told parliament.
"The macabre imagination of the masterminds is limitless," he said in a speech in the lower house of parliament meant to gain approval for an extension of the state of emergency.
The head of Europol, the coordinating organization of EU countries' police forces, said on Thursday that Europe is likely to face new Islamic State attacks after those in Paris on Friday.
"It is reasonable to assume ... that further attacks are likely," Europol director Rob Wainwright told lawmakers in a hearing in the European Parliament in Brussels.
He compared Friday's events in Paris to those in Mumbai in 2008, when militants killed 166 people at different locations across the Indian city.
"The reality of what happened in Mumbai then has now arrived in Europe," Wainwright said.
"This is clearly therefore a more significant and threatening form of terrorism than the phenomenon of the lone actor," he added, referring to attacks over recent years by individuals or small groups inspired by Islamic State.
"It's also a clear statement of intent by ISIS (Islamic State) to export its brutal brand of terrorism to Europe to take it more onto the international stage."
Noting other attacks including last month's downing of a Russian airliner in Egypt, he added: "We are dealing with a very serious, well resourced, determined international terrorist organization that is now active on the streets of Europe. This represents the most serious terrorist threat faced in Europe for 10 years."
The hearing comes on the eve of an extraordinary meeting of EU interior and justice ministers to discuss measures after the attacks in Paris.