French Prime Minister Manuel Valls is warning that the associates of extremists who targeted France last week could use chemical and biological weapons, as he urged Parliament to extend a state of emergency.
Valls presented a bill extending the state of emergency declared after Friday's attacks for another three months to the lower house of Parliament on Thursday. It goes to the upper house Friday.
Valls said "terrorism hit France, not because of what it is doing in Iraq and Syria ... but for what it is."
He added, "we know that there could also be a risk of chemical or biological weapons."
The French military says it has destroyed 35 Islamic State targets in Syria since last week's attacks on Paris.
Military spokesman Col. Gilles Jaron said Thursday that French planes dropped about 60 bombs on six sites, and all the targets were Islamic State command centers or training sites.
He told reporters the strikes were aimed at weakening and disorganizing IS.
France, taking part in the U.S.-led coalition against Islamic State extremists in Syria and Iraq, sharply increased its airstrikes in Syria after Friday's attacks, which killed at least 129.
The Charles de Gaulle nuclear-powered aircraft carrier left Wednesday for the eastern Mediterranean, tripling France's airborne forces in the fight against Islamic State.
Europe is likely to face new Islamic State attacks after those in Paris on Friday, the head of Europol, the coordinating organization of EU countries' police forces, said on Thursday.
"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."
Six raids in Brussels
Meanwhile, authorities in Belgium have launched six raids in the Brussels region linked to Paris suicide bomber Bilal Hadfi.
An official in the Belgian federal prosecutor's office said that the raids were taking place in Molenbeek and other areas of Brussels.
The official spoke on condition of anonymity because the investigation is continuing.
Bilal Hadfi has been identified as one of three attackers at the Stade de France stadium. The raids are centering on "his entourage," the official said.
In Turkey, a government official says authorities have deported some among a group of eight Moroccan nationals who were detained at Istanbul's main airport, while others are still being investigated.
The men were detained on arrival at Ataturk Airport on Wednesday and interviewed by a team of profilers for possible links to Islamic State militants.
The official said in an email sent late Wednesday that authorities have not been able to confirm that the group was attempting to travel to Germany illegally by posing as refugees, as suggested by Turkish media.
The official, who cannot be named because of government rules, said Turkish profiling teams have questioned some 4,700 suspects in the past two years. Around 1,300 people were denied entry into Turkey, while more than 2,300 were deported.
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