Prime Minister Manuel Valls on Thursday warned that France could face chemical or biological attack from terrorist groups.
Valls made the announcement while addressing the French parliament ahead of a vote to extend by three months the state of emergency imposed after the bloody November 13 terror attacks in Paris, BBC reported.
Meanwhile, Belgian police raided six properties in and around Brussels, linked to suspected Paris attackers Bilal Hadfi and Belgian-born French national Salah Abdeslam.
Most of the Belgian raids were targeting properties in Jette and Molenbeek areas connected to Hadfi, a Frenchman living in Belgium who was one of the seven suicide attackers who died in Paris, Belgian broadcaster RTBF reported.
A further raid, in Laeken, is also linked to the Paris attacks that killed 129 people across six locations and injured some 350 others.