PARIS — Restorers at Paris’s fire-damaged Notre Dame cathedral have completed key preliminary work by successfully removing all the perilous roof scaffolding, officials said Tuesday.

The removal of the 200 tons of scaffolding was considered dangerous, with some experts fearing that it could cause more of the Gothic monument to fall down. It was thought that the scaffolding might have melded to the cathedral in the blaze, and be keeping it in place.

When the Notre Dame fire broke out on April 15 last year destroying the spire, the cathedral was already under restoration.

The scaffolding previously installed resisted collapse, “but was deformed by the heat of the fire” Notre Dame restoration officials said in a communique.