A Syrian refugee arrested over the stabbing of a tourist at Berlin's Holocaust memorial had been planning "to kill Jews", prosecutors said on Saturday, the day before an election which is expected to see a surge in support for the anti-migrant AfD.

Police in Berlin say they have arrested a man suspected in a stabbing attack at the city's Holocaust Memorial that left one man seriously injured.

The suspect, a Syrian refugee, told the police that a plan had come into his mind to kill Jews. The attack raises tensions just before an election in which immigration is a big issue.