The irreplaceable collection of Delhi’s National Museum of Natural History was largely destroyed by a massive fire last night, NDTV reports.

Officials confirmed that the fire had broken out on the museum’s sixth floor sometime between 1 and 2 a.m. on Tuesday, when the local fire department was alarmed. The blaze quickly spread throughout the building, and ravaged for almost eight hours before firefighters managed to extinguish the flames. The first and ground floor offices were saved, the Guardian reports.

Safety equipment in the building failed to work, adding to the severity of the damage. “The water system in the building was not working, and we had to arrange for water to be brought from a nearby metro station,” a spokesperson from Delhi’s fire department told the Guardian. “That was the reason there was so much damage. If the water was working we could have saved a lot more of the building.”

According to the paper, among the iconic and extremely rare items in the museum’s collection lost to the fire was a bone from a sauropod dinosaur, estimated to be about 160 million years old.

Fire engulfs Natural History Museum in Delhi. 
Photo: ANI via YouTube.

“This is an irreversible loss,” Rahul Khot, the curator of the Bombay Natural History Society’s collection, told the Guardian. “This is a big loss for society and the nation. Many people use museums for education. It can’t be remade overnight.”

Wall Street Journal India reports that the building which housed the museum in India’s capital was rundown, and plans were made last year to relocate the institution. The Guardian points to a scathing report, published in 2012 by a government-appointed committee, raised serious concerns about the museum’s maintenance. The environment ministry, which manages the museum and its regional branches, had been sharply criticized in the past for the “pathetic functioning” of the museum.

“I have asked for an energy and fire audit of all establishments of the ministry across the country,” said Prakash Javadekar, India’s environment minister. “Plans will be made for how the museum is to be restored. First we have to assess the loss, then we can decide how to restore the museum.”

The cause of the fire is currently being probed by the police.