European security services are searching for at least eight people suspected of being involved in the ISIS attacks on Paris and Brussels, Reuters reports.
Sources told the German Die Welt am Sonntag newspaper that most of the suspects have French or Belgian citizenship but may be in Syria.
The suspects have been in contact with Abdelhamid Abaaoud, the believed mastermind behind the Paris attacks, and Salah Abdeslam, the attack's main surviving suspect. Abaaoud was killed by French police in November and Abaaoud was arrested earlier this month.