At least 10 people were killed and five more were missing after a French high-speed train derailed during a test run on Saturday. The victims were among the team of 49 technicians aboard the train. There were no other passengers. Another 37 people were injured, including 12 people in critical condition. Police said the cause of the crash had not been determined. A source close to the investigation said dozens of technicians were aboard. Saturday’s accident happened with France on high alert following a string of deadly attacks in Paris late Friday.