German police have arrested the suspect of the explosion of Dortmund Borussia  soccer players’ bus, reports BBC.

According to the authorities the explosion was an act of terrorism. “Two suspects from the Islamist spectrum have become the focus of our investigation. Both of their apartments were searched, and one of the two has been detained,” announced the prosecutor’s office.

There were found three letters found at the scene, all of which were written with the same content in German with “Islamist background”.