Six people have been killed and several were injured in a shooting in the southwestern German town of Rot am See, police said on Friday.

A suspect has been arrested and no further suspects are believed to be at large, Aalen police said.

"According to my information, there were six dead and several injured," police spokesman Rudolf Biehlmaier told German broadcaster n-tv.

"We are working on the assumption that this was a single attacker," he said.

Biehlmaier said the initial information suggested the suspect, a German citizen, and one or more of the victims knew each other.

Some of the victims belonged to the same family, he added.

Rot am See is located about 170 kilometres (105 miles) northwest of Munich.