A man who was shot dead in Paris on Thursday after stabbing a police officer with a knife had previously killed a 16-year-old, French media have reported. The Le Parisien newspaper said the 27-year-old attacker, who is believed to have suffered from mental health problems, killed the teenager in an apartment in the north-western suburb of Courbevoie before stealing the victim’s scooter and driving to Paris. The man initially drew the attention of the staff of a luxury store near the Champs-Élysées by walking around with a knife, the newspaper said. When officers attempted to search the 27-year…