MUNICH (Reuters) - German Chancellor Angela Merkel was forced to cancel an election rally in the southern German city of Ingolstadt on Monday after a man took several people hostage in the town hall hours before she was due to speak.

Police said they were in contact by telephone with the man who described himself as armed but had not made any demands. There was no sign of a connection with Merkel's visit, they added.

Merkel's Christian Democrats (CDU) issued a statement saying her pre-election rally with Horst Seehofer, head of the Bavarian Christian Social Union (CSU), had been called off. Germany holds a federal election on September 22 and Bavaria a regional vote one week before that.

"The reason for this is the hostage taking in Ingolstadt," the CDU said of the cancellation.

Authorities evacuated the town hall and closed off the immediate area. Television footage showed emergency vehicles waiting outside the building.

According to the city's website the town hall is a 14th century building, home to the mayor, some administrative posts and the tourist office. Ingolstadt, a city of roughly 125,000 near Munich, is best known as the home of Audi, the luxury unit of German carmaker Volkswagen.

(Reporting by Jens Hack; Writing by Alexandra Hudson; Editing by Noah Barkin)