The group had been detained earlier on Tuesday on suspicion of terrorism near the western city of Aachen.

A spokesman said that they had no specific information to link the five men and two women to last Friday's attacks in Paris.

Police forces across Europe have been on a massive manhunt looking for 26-year-old Salah Abdeslam - a brother to one of the suicide bombers in Paris. Abdeslam had spent several days in Germany in September.

They believe he is part of an "Islamic State" (IS) linked sleeper cell operating in Europe.

Tuesday's developments in Germany followed several arrests in France and Belgium following the mass killings.

First, two women and one man were arrested close to a job center in the town of Alsdorf at around 9:30 am local time (08:30 UTC).

Later four more people were detained at another location in Alsdorf, police said.

Officials confirmed that at least three of those arrested were foreign nationals.

Aachen is a university town with 250,000 residents near Germany's border with the Netherlands and Belgium. The city is only 160 kilometers (100 miles) east of the Belgian capital Brussels, from where the Paris attacks appeared to have been organized.

Earlier, German Interior Minister Thomas de Maiziere said the arrests did not appear to be "directly" linked to the Paris attacks.

"We had received some tip-offs indicating that one of the individuals sought in connection with the events in Paris was in our jurisdiction," a police official said at the time of the arrests.

Special units had been deployed to carry out the operation.

Stadium sealed

Separately, police briefly sealed off Hannover's football stadium where a friendly match between Germany and the Netherlands was due to take place, after a suspicious suitcase was found.

The doors were later opened for fans.

German Chancellor Angela Merkel and several cabinet ministers are expected to attend the match.

Germany was playing France in a friendly on Friday when suicide bombers attempted to enter the Stade de France, as well as other attacks around Paris.

mm/kms (DPA, Reuters)