Germany's justice minister on Monday warned against drawing a hasty link between refugees and perpetrators of the deadly Paris attacks, warning that the IS group could be trying to exploit the debate over Europe's migrant influx.

The French police's discovery of a purported Syrian passport near the body of one attacker in particular has sparked concerns that at least one of the assailants might have entered Europe with the hundreds of thousands of people fleeing Syria's civil war.

But Justice Minister Heiko Maas called for "very, very great prudence, until things are clear".

"We are aware that the IS (Islamic State) is known to leave such false tracks behind to politicise and radicalise the issue over refugees in Europe," Maas told public broadcaster ARD.

Both Interior Minister Thomas de Maiziere and Defence Minister Ursula von der Leyen had came out over the weekend to urge caution against linking the attackers to the record influx of migrants to Europe.

"I would like to make this urgent plea to avoid drawing such swift links to the situation surrounding refugees," de Maiziere said.

Von der Leyen, for her part, pointed out that "terrorism is so well organised that it does not need to take the difficult route taken by refugees, who risk their lives by crossing the high seas."

The questions over Europe's migrant influx are particularly sensitive in Germany, which has become the top destination for those fleeing war and persecution.

Europe's biggest economy expects to see around one million asylum seekers this year alone.

While a majority of Germans have largely supported Chancellor Angela Merkel's welcoming stance, the new arrivals have also sparked a backlash in some quarters including a spate of arson attacks against refugee shelters.

The interior ministry has said that security would be beefed up at asylum seeker homes after the Paris attacks.