Paris - A water leak in late November damaged several hundred works in the Louvre's Egyptian department, the iconic Paris museum told AFP on Sunday, weeks after a brazen jewel theft raised concerns over its infrastructure.

"Between 300 and 400 works" were affected by the leak discovered on November 26, said the museum's deputy administrator Francis Steinbock, describing them as "Egyptology journals" and "scientific documentation" used by researchers.

The damaged items date from the late 19th and early 20th centuries and are "extremely useful" but are "by no means unique," Steinbock added.

"No heritage artefacts have been affected by this damage," he said, adding: "At this stage, we have no irreparable and definitive losses in these collections."

The incident follows the remarkable October heist in which a four-person gang raided the world's most-visited art museum in broad daylight, stealing jewelry worth an estimated $102 million in just seven minutes before fleeing on scooters, sparking debate over the museum's ageing infrastructure.

At least five people have been arrested over the heist, but none of the jewels have been recovered.

The Louvre's most senior officer announced 20 "emergency measures" had been implemented in November to bolster security at the sprawling facility, but provided little detail as to what they were.

The Louvre said there would be an internal investigation into the November leak, which was caused by the accidental opening of a valve in the heating and ventilation system that led to water seeping through the ceiling of the Mollien wing, where the books were stored.

The "completely obsolete" system has been shut down for months and is due to be replaced from September 2026, the museum administrator added.

As for the works, they will "be dried, sent to a bookbinder to be restored, and then returned to the shelves," he added.

In late November, the Louvre said it would raise ticket prices for most non-EU visitors, meaning U.S., British and Chinese tourists among others will have to pay 32 euros (about $37) to get in.

The museum told AFP the 45% price hike aims to boost annual revenues by up to $23 million to fund structural improvements at the cultural institution.

The Louvre is the world's most-visited museum, welcoming 8.7 million visitors in 2024, 69% of them from abroad.