Paris attack ringleader Salah Abdeslam was hiding in a Brussels flat in Belgium, said emerging reports.
Belgian federal prosecutors on Friday said that Abdeslam's fingerprints were found inside the apartment in Schaerbeek borough during a raid conducted on 10 December, AFP reported.
The police have also reportedly recovered bomb-making materials, three hand-made belts and suicide vests from the flat.
Traces of unstable explosive material called TATP (triacetone triperoxide) were also found and the same was used in the Paris attacks.
The flat was rented by one of the suspects arrested in Brussels, said Eric Van der Sypt, who is the spokesman for the prosecutors. However, he declined to identify the suspect in custody.
The police believe that the terrorists manufactured the explosives in the third-floor apartment. It is also believed that the Paris attack was plotted in Belgium.