One person has been killed and several police officers injured in a knife attack in France that President Emmanuel Macron has described as "Islamist terrorism". A man shouting "Allahu Akbar" ("God is greatest") launched the attack at a packed market in the eastern city of Mulhouse on Saturday afternoon, France's anti-terrorism prosecutor's office said. A 37-year-old Algerian man was arrested, according to the prosecutors' office, which is investigating the stabbings. The suspect had been on a list of people flagged for radicalism, the regional prosecutor said. The victim was a 69-year-old Portuguese man, prosecutors revealed. Mr Macron branded the knifeman "an Islamic extremist", saying: "It is without any doubt an act of Islamist terrorism." The government had "complete determination" to respond to the attack, he said, and also expressed "the solidarity of the nation" with those attacked and their loved ones.