Johann Vexo, the organist who was playing at evening mass inside Notre Dame when flames began licking at the iconic cathedral's roof, poses at the pipe organ at Notre Dame de Nancy cathedral, eastern France, Wednesday, April 17, 2019. Vexo , who was playing at evening mass inside Notre Dame when flames began licking at the iconic cathedral's roof says people didn't immediately react when the fire alarm rang as a priest was reading from the Bible. (AP Photo/Oleg Cetinic)

Johann Vexo, the organist who was playing at evening mass inside Notre Dame when flames began licking at the iconic cathedral's roof, pllays the pipe organ at Notre Dame de Nancy cathedral, eastern France, Wednesday, April 17, 2019. Vexo , who was playing at evening mass inside Notre Dame when flames began licking at the iconic cathedral's roof says people didn't immediately react when the fire alarm rang as a priest was reading from the Bible. (AP Photo/Oleg Cetinic)