Germany's Interior Ministry said Sunday that over 100 members of the so-called "Islamic State" (IS) terrorist group have returned to the country following the jihadi networks failed incursions in Iraq and Syria.

"Security authorities obtained knowledge that they actively engaged in combat in Syria and Iraq or have completed apprenticeships to this end," the ministry told the DPA news agency. "These people remain under police and judicial investigation."

The ministry added that the number of open investigations is in the "two-figure range."

Authorities believe that 1,060 IS fighters left Germany for Syria or Iraq, of which a third have since returned, the Interior Ministry said.

German authorities are taking a "holistic approach" to the handling of the returnees, which besides criminal prosecution includes deradicalization and reintegration, according to the ministry.

Read more: Prosecuting IS returnees in Germany requires the law's longest arm

Others in custody abroad

Several suspected German IS members are believed to be in custody in Iraq, Syria or Turkey.

Turkish authorities have called on Germany and other European countries to take back IS suspects, with Turkish Interior Minister Soleyman Solyu saying in November that Turkey is not "a hotel for IS members."

On Thursday, German authorities arrested two women, one of which was a suspected IS member, upon their arrival at Frankfurt Airport from Ankara after they were deported by Turkey.

According to the Genocide Network, a genocide investigation body backed by the European Union, many returning suspected IS fighters only face domestic terrorism charges in their home countries, which come with a statute of limitations that sets a time limit to prosecution.

The body has called for European authorities to add war crimes and genocide charges, the most serious crimes under international law which could lead to longer sentences.

dv/mm (AFP, dpa)

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