The Isis militant group could arm itself with biological and chemical weapons in future terror attacks on Europe, the French prime minister has warned.
Manuel Valls said France faced a serious threat from associates linked to the gunmen and bombers who launched attacks across Paris last Friday, killing 129.
"We must not rule anything out," he said. "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."
Mr Valls presented a bill to the French parliament that would extend the country's state of emergency for another three months. It will then go to the upper house on Friday.
He said: "Terrorism hit France, not because of what it is doing in Iraq and Syria ... but for what it is."
Meanwhile, the French Interior Ministry and Paris prosecutor's office said it remains unclear whether the suspected mastermind of last week's Paris attacks was killed in a raid on Wednesday or is still at large.
Officials said authorities are working on determining whether 27-year-old Belgian Abdelhamid Abaaoud was among those killed in a chaotic and bloody raid on an apartment in the Paris suburb of Saint-Denis, which left two dead and seven in custody.
Police launched the operation after receiving information from tapped phone calls, surveillance and tip-offs suggesting Abaaoud was holed up there.
Paris prosecutor Francois Molins said the identities of the dead - including a female suicide bomber - are still being investigated, but that neither Abaaoud nor another fugitive, Salah Abdeslam, is in custody.
Additional reporting by agencies
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