Workers are seen on top of the burnt Notre-Dame Cathedral in Paris, capital of France, April 24, 2019. The person in charge of checking the fire alarm did not go to the right place after Notre-Dame Cathedral in central Paris caught fire on April 15, French news channel BFMTV reported on Wednesday, citing a source close to the investigation. The first alarm was triggered at 6:20 p.m. local time on April 15, the report said. The second alarm sounded 20 minutes later, but it was already too late since the fire has begun to spread. In another development, French weekly Le Canard Enchaine reported that workers renovating Notre-Dame Cathedral had smoked on site. (Xinhua/Gao Jing)