Paris' Notre Dame Cathedral up in flames

A photo from 1880 shows Notre Dame towering over central Paris. Until the Eiffel Tower was unveiled for the 1889 World's Fair, Notre Dame was the tallest structure in the French capital.

Statues overlooking the cathedral's roof, which was almost entirely destroyed in the blaze.

Quasimodo, the fictional character and main protagonist in Victor Hugo's 1831 novel "The Hunchback of Notre Dame," made the world-renowned cathedral even more famous. The book was made into numerous films. Here, Quasimodo is seen ringing the church bells in the 1956 French-Italian version directed by Jean Delannoy.

Security forces sealed off the area around the cathedral as some 400 firefighters used powerful hoses in an effort to bring the flames under control. The cathedral was undergoing restoration works when the fire started. Investigators are treating the cause of the fire as an accident, ruling out arson or terrorism.

The fire caused the spire to come crashing down and the wooden roof support structures to go up in flames. The cathedral building had fallen into ruin after years of neglect following the French Revolution, but was saved thanks to a vast restoration campaign that began in the 19th century.

The blaze burned for nearly eight hours before it was contained.

Firefighters were able to prevent the fire from spreading to Notre Dame's two towers and belfry. Officials said after several hours of intense operations that the basic structure had been "saved and preserved."

People in Paris looked on in horror, prayed and sung hymns as fire took hold of more and more of the cathedral. "Paris is disfigured, the city will never be like it was before," one man (not pictured) told French news agency AFP. "It's a tragedy," he added. "If you pray, now is the time to pray."

The responders fought to save the artwork at the back of the famous cathedral. Many priceless artworks and cultural relics were taken out before being burned. Last week, by chance, workers had removed 16 copper statues for cleaning for the first time in over a century.

An aerial view shows firefighters battling the raging fire. A part of the vault collapsed and only a part of the interior was destroyed.

In the early morning hours, the first images of the interior emerged. Paris Mayor Anne Hidalgo and French President Emmanuel Macron entered the building. Hidalgo said "there is no roof anymore, there's none of that left" — but that the interior was in much better condition than she and others had expected.