Customs agents seized 45 paleontological pieces at an airport in western Argentina that were being transported by a private plane that arrived from Colombia, officials said Thursday.

The fossils, which were found during a routine inspection at an airport in Mendoza province, "date back millions of years and have an important cultural and historical value," the Federal Public Revenue Administration, or AFIP, said in a statement.

"On observing what appeared to be strange stones, the agents suspected they were not dealing with conventional pieces and called for the assistance of official experts," the AFIP, which oversees the customs service, said.

Prosecutors will determine "the legal situation" of the pieces and who they belong to, the AFIP said.

Argentine law punishes the smuggling of antiquities with prison terms of two months to two years. EFE