European Union counter-terrorism chief Gilles de Kerchove today said that there was no absolute way to prevent new terror attacks like those in Paris.
"We can't prevent (such attacks) 100 per cent," Kerchove said.
He said the answer was not to jail jihadists returning to Europe from Syria and Iraq, as prisons had become "massive incubators" of radicalisation.
"The threat remains serious," said de Kerchove in an interview to AFP, who met with European, US and Canadian security ministers in Paris on Sunday after the Islamist attacks in the French capital last week in which 17 people were killed.
He said the Islamic State group, which is being attacked by US-led forces in Iraq and Syria, has said it wants to attack western targets while a "strongly degraded" Al-Qaeda wants to remain a force to be reckoned with.
He warned that the Al-Nusra Front, the Al-Qaeda branch in Syria, is also looking for "clean skins," Europeans with no record of radical activity, to mount attacks in Europe.
