Investigators believe the fire which engulfed Notre Dame cathedral in Paris earlier this week was caused by an electrical fault, Daily Mail reports.
Speaking anonymously, a French official said an examination team had been brought in to determine the source of the blaze despite the concerns about the integrity of the fragile structure which is still being bolstered with supportive scaffolding.
WATCH this video to see the shocking extent of the fire
On Thursday, French police released time lapse footage from a camera installed hours before the inferno broke out at around 6.40pm Monday evening.
The fire destroyed the iconic roof of the cathedral, whose oak beams date back to the 13th century.
Investigators hope the video shots will help them understand the timeline of the disaster.
Notre Dame was undergoing reconstructive work from five companies including Europe Echafaudage before the fire consumed much of the medieval monument.
Notre Dame is one of the world's finest landmarks and an important place of worship for both Parisian Catholics and international visitors.
Paris' public prosecutor Remy Heitz made a statement declaring the fire appeared accidental.