An international investigation into antiquities looted from India and smuggled into the United States has taken authorities to the Honolulu Museum of Art.

The museum on Wednesday is handing over seven rare artifacts that it acquired without museum officials realizing they were ill-gotten items. Agents from the U.S. Immigration and Customs Enforcement will take the items back to New York and from there, eventually return them to the government of India.

U.S. customs agents say the items were taken from religious temples and ancient Buddhist sites, and then allegedly smuggled to the United States by an art dealer. The dealer, Subhash Kapoor, was arrested in 2011 and is awaiting trial in India. Officials say Kapoor created false provenances for the illicit antiquities.

Last year, an antique sculpture was handed over to Indian diplomats at a Manhattan ceremony.

The investigation is dubbed “Operation Hidden Idol,” involving four arrests and the recovery of thousands of pieces worth $150 million.

Agents are hailing the Honolulu museum for being the first U.S. institution to publicly and easily cooperate with the investigation. When agents informed the museum that a 2,000-year-old terra cotta rattle might have found its way into its collection, museum officials identified six other Indian pieces, said Lou Martinez, a spokesman for ICE in New York.

Martinez stressed there’s no culpability on the museum’s part, as it wasn’t aware of the items’ provenance when it received them as gifts and purchased them between 1991 and 2003.

“Looting is a serious problem in the art market and all buyers of art, including museums, need to be mindful that some antiquities have been illegally obtained,” said Stephan Jost, director of the Honolulu Museum of Art. “Over the past several years, American art museums have become progressively more rigorous in vetting the history of objects they acquire. Clearly the museum could have done better in the past.”

In addition to the rattle, the objects include figurines, architectural fragments and tiles.

It’s very rare for evidence to come to light to show a museum has items that were illegally obtained, said James Cuno president and CEO of the J. Paul Getty Trust. “Claims might come from time to time but most often those claims are based on just interest or the construction of national identity,” he said. “If evidence is provided that’s convincing, no museum will resist.”

He cited an example from about 10 years ago when Italian police uncovered evidence revealing some items were improperly removed from Italy. The U.S. museums where some items ended up returned them, he said.

Repatriation has become more common in the past couple of decades, said Malcom Bell, a professor of Greek and Roman art and archaeology at the University of Virginia. He said that as a general rule of thumb, museums and art collectors avoid purchasing items exported without clear and valid documentation before 1970 — the year of a United Nations cultural agreement targeting trafficking in antiquities.

“Transparency is important and if the Honolulu museum has been open, that’s probably to be applauded,” he said.