The attack on a French police officer outside Paris's famed Notre Dame cathedral by a hammer-wielding man was an "isolated act," government spokesman Christophe Castaner said Wednesday. 


Tuesday's attacker had "never showed any sign of radicalisation," he told RTL radio, but stressed that the investigation was at an early stage. 


Castaner said the man, who was shot and injured by police, "had at no moment showed signs of radicalisation." 


The officer sustained minor neck injuries in the assault, which comes with France on high alert after jihadists killed seven people in London on Saturday. 


Documents found on the attacker identified him as a 40-year-old Algerian who was a doctoral student in information science at a university in the east of France. 


The suspect later claimed to be a "soldier of the caliphate" of the Islamic State group, according to a source close to the investigation. 


The policeman's colleague opened fire on the man, hitting him in the chest in panicked scenes around the Gothic cathedral that is one of France's most visited tourist attractions

Source: NNA