German authorities say they have arrested a Syrian jihadist suspected of a war crime in relation to the abduction of a UN peacekeeper. The 24-year-old – identified only as Suliman AS – was held at an address near Stuttgart, the prosecutor office said. The apartment was subsequently searched by police.

Suliman is suspected to have been a member of al-Qaeda's Syrian offshoot Jabhat al-Nusra when the group kidnapped a UN employee near Damascus in February 2013. The victim was part of the UN peacekeeping mission in the Golan Heights, off the border between Israel and Syria.

His captors repeatedly issued death threats against him in an effort to secure a ransom but he eventually managed to escape in October that year. Suliman allegedly worked as a jailer for al-Nusra, directly guarding the hostage for the four months running from March to June 2013.

The kidnapping is considered a war crime as it targeted a UN peacekeeping mission.