A Virginia fossils dealer was sentenced Tuesday to three months in jail even after a prosecutor described his cooperation with law enforcement in heroic terms, saying he enabled more than 18 largely complete dinosaur fossils to be located, enough for Mongolia to open its first dinosaur museum.

Eric Prokopi, 39, was sentenced by Southern District Judge Alvin Hellerstein (See Profile) for smuggling a 70-million-year-old Tyrannosaurus skeleton from Mongolia into the United States by making false statements to U.S. officials, including that the then-unassembled bones were merely reptile fossils from Great Britain.

Once assembled, the skeleton was sold by Dallas-based Heritage Auctions for more than $1 million before it was seized by the U.S. government and returned to Mongolia.

Hellerstein also ordered Prokopi to serve three months community confinement and 100 hours of community service.

Hellerstein said Prokopi was to be commended for his cooperation and for working as a commercial paleontologist to enhance the world’s knowledge of the origins of man.

But the judge said Prokopi had “done a bad thing” and needed punishment.

Prokopi apologized and said he hoped to rebuild his business with an emphasis on getting proper documentation for bones he purchases.

“I sincerely love fossils,” said Prokopi, of Williamsburg, Va.

Defense attorney Georges Lederman had asked the judge to spare Prokopi from prison, citing his cooperation and noting that the charges had led to his divorce, the loss of his home and a stigma that had caused others in his profession to resist working with him.

Assistant U.S. Attorney Martin S. Bell said Prokopi’s knowledge had aided investigations into the dinosaur fossil trade that were continuing in Wyoming, California and New York.