A French judicial police official said investigators think an electrical short-circuit most likely caused Notre Dame Cathedral fire.

The official, who spoke anonymously about the ongoing investigation, said investigators still don't have the green light to work in the cathedral and search in the rubble for safety reasons.

He told The Associated Press the monument is still being consolidated with wooden planks to support some fragilize parts of the walls.

Earlier, a Paris official said part of the support structure around Notre Dame Cathedral's rose windows will be dismantled to prevent further damage following a massive fire.

The Culture Ministry's fire expert, Jose Vaz de Matos, told reporters that part of the triangular structure above the central rose window is to be taken down "to limit the movement" of the stone.

De Matos said the main risk to the cathedral is the gables above the rose windows, which provide crucial support to the stained glass masterpieces.

He said the structure is particularly exposed to the wind, and the overall structure remains fragile.

Police officials told The Associated Press that the triangular structure is leaning 20 centimeters forward toward the street since the fire.

Firefighter spokesman Gabriel Plus said firefighters took down statues inside the gables above the rose windows to protect them, and took care not to spray water too hard on the delicate stained glass.

The Paris prosecutor's office says investigators looking into the causes of the Notre Dame fire have still not been able to look inside the cathedral, as it remains unsafe.

Investigators will continue with interviews Wednesday, saying the inquiry will go on until prosecutors uncover "the truth and identify the origin" of the blaze. On Tuesday, investigators spoke with around 30 witnesses, including employees of companies involved in the church's restoration and security personnel.

Nearly $1 billion has already poured in from ordinary worshippers and high-powered magnates around the world to restore Notre Dame Cathedral.

Construction teams brought in a huge crane and a delivery of planks of wood to the site Wednesday morning.

French President Emmanuel Macron ratcheted up the pressure by setting a five-year deadline to restore the 12th-century landmark. Macron is holding a special Cabinet meeting Wednesday dedicated to the Notre Dame disaster.

Presidential cultural heritage envoy Stephane Bern told broadcaster France-Info on Wednesday that 880 million euros ($995 million) has been raised so far. Contributors include Apple and magnates who own L'Oreal, Chanel and Dior, as well as Catholics and others from around France and the world.

Authorities consider the fire an accident.

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