A suspected right-wing extremist shot dead nine people, including several migrants from Turkey, in an overnight rampage near the German city of Frankfurt before killing himself, officials said.
The presumed killer was a 43-year-old German man who held a firearms licence and was a member of a gun club.
The police chased a car used to leave the scene, where they found his body and that of his 72-year-old mother, said Peter Beuth, interior minister of Hesse state.
For her part, Chancellor Angela Merkel condemned the attack which targeted two shisha bars in Hanau.
She told reporters it appeared to have been motivated by the "poison" of racism that was to blame for "too many crimes."
In Western countries, shisha bars are often owned and operated by people from the Middle East or South Asia, Reuters reported.
Federal prosecutors said they had taken charge of the case due to its likely extremist motive, and newspaper Bild said the suspect had expressed far-right views in a written confession.
For his part, Turkey's ambassador in Berlin, Ali Kemal Aydin, told state broadcaster TRT Haber that five Turkish nationals were among the dead.
"We expect German authorities to show maximum effort to enlighten this case. Racism is a collective cancer," Turkish presidency spokesman Ibrahim Kalin said earlier on Twitter.
The Confederation of the Communities of Kurdistan in Germany said several victims were Kurdish, expressing anger that Germany's political leaders "are not resolutely opposing right-wing networks and right-wing terrorism."
According to Reuters, Germany, which is home to three million people of Turkish origin including one million ethnic Kurds, has seen its political landscape polarised in recent years, with a wave of immigration and a slowing economy helping to fuel support for extremist groups at both ends of the spectrum.
Police said there were no indications that other suspects were involved in the Hanau attack. They said investigations into the identity of gunman and victims were ongoing.
