A major rift has opened up between German Chancellor Angela Merkel and her interior minister over migrant policy, threatening her coalition government. The minister, Horst Seehofer of the Christian Social Union (CSU), wants police to have the power to turn away undocumented migrants at the border. Mrs Merkel has held emergency talks with her Christian Democrat (CDU) MPs. She wants a new deal at EU level over migrants. She was widely criticised for letting in about one million in 2015.