The Islamic State (IS) militant group has threatened to attack Germany and Chancellor Angela Merkel, according to a video posted online on Wednesday, AFP reported.

In the five-minute video two German-speaking men claiming to represent the jihadist group call on their « brothers and sisters » in Germany and Austria to launch attacks on “infidels’’ or join the IS fighters in Syria and Iraq.

One of the men in the video threatens Chancellor Merkel over the presence of German troops in Afghanistan as part of a NATO-led training and advisory mission and their support for the coalition against IS, AFP said.

Some 600 Germans have joined jihadist groups in Syria and Iraq, the newswire said, citing German intelligence estimates.

Earlier on Wednesday, the head of Germany‘s domestic intelligence agency BfV Hans-Georg Maassen said that the flow of people travelling to Iraq and Syria to join the Islamic State group is slowing.

“This year the number of people leaving [for Iraq and Syria] has increased, but not at the same rate,” Maassen told Reuters.