The large skeletons, which had been preserved at Tan Temple for about 300 years, were restored and put on display in 2022 under a project costing more than VND 14 billion (approximately USD 532,000).
Measuring 22 metres and 18 metres in length, each skeleton is made up of about 50 vertebrae and 28 ribs. Officials said parts restored during the project have begun to peel, develop mould and decay.
The Ly Son special administrative zone Centre for Communications, Culture and Sports said the skeletons were already badly damaged before restoration, particularly the skulls, leading to resin treatment and composite reconstruction in 2021.
An inspection in January found several composite sections had deteriorated and flaked off, affecting the display, while the original bones remain relatively well preserved.
Authorities have proposed setting up an inspection team to assess the extent and causes of the damage and recommend conservation measures to ensure visitor safety and protect the exhibits’ historical and cultural value.