Notre Dame Cathedral fire: Timeline

PARIS — The iconic Notre-Dame Cathedral caught fire on Monday, destroying the landmark's roof and causing its famous steeple to collapse. Here is a timeline of how the fire occurred.

According to The Guardian, smoke alarms sounded off during mass at 6:20 p.m. on April 15. The priest continued the service, believing it was a false alarm. Soon after, the building was evacuated as a precaution.

By 6:43 p.m. a second alarm had gone off and firefighters had been called in as the flames were quickly spreading to the cathedral's roof. Fire chief Jean-Claude Gallet told the New York Times that the fire began in the cathedral's attic.

According to Reuters, at 7:40 p.m. the fire had spread to the 850-year-old cathedral's famous spire. Minutes later, the spire collapsed in its entirety. By 8:07 p.m. the roof of the cathedral had also collapsed.

According to Reuters, at 8:25 p.m. Parisian police had started to evacuate Paris' Ile de la Cité, the island where the cathedral was built. The Guardian reports that around 9 p.m. the fire had reached the north tower.

By 9:40 p.m., Gallet told The Guardian there were 400 firefighters, two helicopters and two water tankers attempting to extinguish the fire.

Fire services announced that the fire had been completely extinguished the next morning at around 9:30 a.m.

According to Fortune, the following artifacts have been recovered from the fire so far: The Crown of Thorns, the Tunic of Saint Louis, the Rose Windows, the Great Organ, the Notre-Dame Bells, the bronze statues of the Twelve Apostles, and a few paintings.