BERLIN (AFP) - A German court Friday jailed a militant for three years and nine months in the country's first trial of a member of the Islamic State in Iraq and Syria (ISIS) group.

Kreshnik Berisha, 20, born near the business capital Frankfurt to a family from Kosovo, was found guilty of membership in a foreign terrorist organisation, said presiding judge Thomas Lagebier.

Berisha had admitted in court to having joined ISIS and taken part in fighting in Syria.

The prosecution had called for a sentence of four years and three months, while the defence had urged a lesser term of three years and three months.

Federal prosecutors had told the court that Berisha travelled to Syria via Turkey in July 2013 with other Islamists planning to join the fight to create a "caliphate" straddling Syria and Iraq.

He returned home for unclear reasons in December 2013 and was arrested at Frankfurt airport.

The trial opened in September.

Germany's domestic intelligence service believes about 550 German nationals have joined the ISIS in Syria and Iraq, 60 have died there in combat or suicide attacks, and 180 have returned to Germany.