PARIS - A person known to the French authorities as a radical Islamist with mental health troubles stabbed a German tourist to death and wounded two people in central Paris on Saturday before being arrested, officials said. The attack took place close to the Eiffel Tower during a busy weekend night and came with the country on its highest alert for attacks as tensions rise against the background of the war between Israel and Hamas. “We will not give in to terrorism,” Prime Minister Elisabeth Borne wrote on X, formerly Twitter, after the attack. President Emmanuel Macron said he was sending his condolences to the family of a German killed in the “terrorist attack”. French anti-terror prosecutors said that they would now take on the investigation. The attacker was known to authorities as a radical Islamist and was being treated for mental illness, Interior Minister Gerald Darmanin said at the scene by the River Seine, adding that the man had shouted “Allahu Akbar” (“God is greatest”) before being arrested. He fatally stabbed the German tourist, born in 1999, with a knife and then used a hammer to attack others as he sought to escape on the other side of the River Seine. The area by Bir Hakeim bridge, usually thronging with tourists and locals, was cordoned off by police and bright with the flashing lights of security forces and emergency services. The Paris prosecutor’s office said the attacker, born in 1997, is French and has been arrested in an investigation into murder and attempted murder.