PARIS — A shooting in the French city of Strasbourg killed two people and wounded up to eight others, officials said, sparking a major security operation around a world-famous Christmas market on Tuesday. Authorities said the shooter remains at large. The motive for the shooting is unclear. It wasn’t immediately clear if the market was the target of the attack or if there was any link to terrorism. Interior Minister Christophe Castaner told reporters that the gunman has been identified, and had a police record for common crimes.