Two white tigers have reportedly died at a Crimean zoo during a two-week blackout, according to reports.

On Friday, the Associated Press reported that one six-week-old white Bengal tiger cub died after a generator broke down. Oleg Zubkov, director of the zoo in the Black Sea resort of Yalta, said at the time:

“We’ve failed to maintain the temperature regime. These were white Bengal tiger cubs, they are very particular about the warmth.”

On Sunday, Russian news sources reported that yet another tiger cub, the brother of the first, died in the blackout as well, as the zoo has not been able to keep the animals warm enough.

With this death, however, Zubkov refused to blame the cold. He said in a translated interview with the Russian News Agency:

“It’s hard to say that this is caused by hypothermia. White tiger cubs are very weak by nature, and even more so when they’re still on the bottle.”

He said that the zoo is performing an autopsy to determine the cause of death. The facility is currently only being fueled by two small gasoline generators.

Crimea’s prosecutor general said that the zoo should have bought diesel generators to prevent the death. Crimea is currently facing an electricity crisis, with some 10 percent of its population of 2 million without power. The blackout is being attributed to the damage to electricity pylons reportedly done by anti-Russian activists. The blackout comes in the wake of Russia’s annexation of Crimea from Ukraine in 2014.

It’s worth mentioning that while most media reports refer to the animals as “rare,” white tigers are not a species, but rather a manmade hybrid of tigers, many of whom share the same few ancestors. The animals are often interbred by zoos and parks to keep their distinctive white coats, and are subject to severe genetic mutations and hereditary problems.

[Image via Getty]