Russian investigators stopped the attempted smuggling of a massive meteorite fragment to the United Kingdom after it was falsely declared as a garden sculpture, customs officials said.

The 2.8-ton object is believed to be part of the Aletai meteorite, one of the largest known iron meteorites, and prosecutors have launched a criminal investigation.

Authorities discovered the item during an inspection of a sea container at the port of Saint Petersburg and later found its declared origin and value were false.

The fragment is estimated to be worth about 323 million rubles ($4.2 million), though officials did not identify who tried to export it, CBS News has reported.

Scientists note that meteorites like Aletai, discovered in China in 1898 and dating back 4.5 billion years, are ethically sensitive due to their scientific importance.