(VOVworld) - The German foreign ministry has warned about possible attacks on Istanbul's underground rail network and bus stops in the wake of Turkey's assault on Kurdish armed groups in northern Iraq.

(Photo: AFP/ VNA)

The foreign ministry said on its website on Wednesday that there could be increased attacks by the Kurdistan Workers Party. The German government warned its citizens to avoid the border between Syria and Iraq. Christiane Wirtz, German Deputy Government Spokesperson, said the instability in Turkey and terrorism threats have intensified tension in this country.