Friedrich Merz says he will boost border controls if he wins power in next month’s elections

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Germany’s opposition leader has pledged to strengthen border controls and step up deportations if he becomes chancellor after elections next month, a day after an Afghan man was arrested over a knife attack in which two people died.

Friedrich Merz, whose conservative CDU/CSU alliance is leading in polls, said he would not allow attacks like the one in the Bavarian city of Aschaffenburg on Wednesday to become a “normal affair”.