An unknown Iraqi group has issued a video showing four Western aid workers kidnapped in Iraq on Saturday.The tape was released to Al Jazeera by a group calling itself Swords of Truth. It describes the four men sitting on the ground as “spies of occupying forces”. The name of Norman Kember can be seen on a British passport in the video. Meanwhile, another group of kidnappers have threatened to kill a German woman and her driver unless Berlin stops cooperating with Iraqi authorities. The hostage has been identified has Susanne Osthoff, a 43-year old archeologist who speaks flent Arabic. In response to the threat, German authorities have set up a crisis committee. German Foreign Minister, Frank Walter Steinmeier says he is “gravely concerned” about her fate. “The government is doing everything it can to protect and ensure the hostages’ safe return,” he says. Berlin will not be sending any troops to Iraq, but it will continue to train its security forces outside of the country. Susanne’s mother Ingrid has also spoken of her daughter’s devoution to the people of Iraq and appealed for her safe release. She says Susanne’s been living and doing aid work in the country for a long time. “Her heart and soul are in Iraq and have been since she was young, she says. “The people were nice and she loved being there,” she added.