Thousands of tropical fish reportedly have died at a Russian airport after being held in customs for 15 hours in the summer heat.

The state RIA Novosti news agency says more that 4,000 fish worth $480,000 died in the Black Sea resort of Sochi after customs officials spent 15 hours clearing the cargo Saturday. The fish had been shipped from China and made a brief stop in India.

The fish were intended for Sochi Discovery World, Russia's largest oceanarium, which is slated to open this month.

RIA Novosti's report Tuesday quotes Oceanarium director Amin Azzam as saying the loss of the fish is an "atrocity unseen anywhere else in the world."

The $25 million oceanarium is part of the development before the 2014 Winter Olympics in Sochi.