For more than 20 years, a group of criminals orchestrated a string of high-profile thefts of valuable artworks and sports memorabilia, including pieces by Andy Warhol and Jackson Pollock, and Yogi Berra’s World Series rings.

Now, the United States Attorney’s Office for the Middle District of Pennsylvania has charged nine suspects in the robberies, which began in 1999 and largely targeted institutions and antique shops in Pennsylvania, New Jersey, and upstate New York. The charges are conspiracy to commit theft of major artwork and interstate transportation of stolen property.

Most of the thefts were sports-related, but also included Warhol’s Le Grande Passion and Pollock’s Springs Winter (1949), stolen in 2005 from the Everhart Museum of Natural History, Science, and Art in Scranton. Some of the pilfered objects have since been recovered, but the Scranton artworks remain missing.

“We would love to be able to host an exhibit that’s called: ‘Art once stolen, but now returned,’” museum director Charles Barber told the New York Times.

The U.S. Attorney’s Office showed these images of the stolen Andy Warhol and Jackson Pollock artworks from the Everhart Museum in Scranton at a press conference announcing charges in a string of museum robberies that lasted over 20 years.

At the time of the crime, the Pollock canvas was worth an estimated $11.6 million and the Warhol silkscreen was worth $15,000. (The latter is valued at about $100,000 in the new indictment.)

Another high-value target was a $1 million collection stolen in 2014 from the Yogi Berra Museum and Learning Center in Little Falls, New Jersey. The alleged thieves snatched nine of his 10 World Series Rings plus two MVP plaques, and seven other championship rings won by the famed baseball player.

In 2010, the gang also appears to have hit Scranton’s Lackawanna Historical Society, making off with a Tiffany Lamp from 1903 or 1904. In 2006, they snatched three antique firearms collectively worth $1 million from Space Farms: Zoo and Museum in Wantage, New Jersey. A decade later, they struck the Roger Maris Museum in Fargo, North Dakota, stealing an MVP plaque and a solid gold Hickok Belt, encrusted in jewels.

Also among the more than 20 institutions victimized in the string of heists are the International Boxing Hall of Fame in Canastota, New York, (six 1940s and 1950s championship belts stolen in 2015) and the Harness Racing Museum and Hall of Fame in Goshen, New York (14 trophies taken in 2012).

Andy Warhol, La Grande Passion. Thieves stole a copy of this silkscreen from the Everhart Museum in Scranton in 2005. Collection of the Whitney Museum of American Art, New York; gift of Carillon Importers, Ltd. The Andy Warhol Foundation for the Visual Arts, Inc.

Officials believe that the band of thieves melted down the stolen rings and trophies to create metal bars that could be easily sold. According to the indictment, the thieves made hundreds of thousands of dollars, but also sold the gold for much less than its true value.

Efforts to track down as many of the stolen valuables as possible remain ongoing. “We will do whatever we can to return them to their rightful owners and their rightful places,” Christopher Paris, commissioner of the Pennsylvania State Police, told a local FOX affiliate.

Only one or two thieves appears to have been present at each break in, with a larger crew orchestrating the planning for each heist. A key clue in identifying the suspects was DNA evidence left at the boxing museum when one of the thieves cut himself breaking into a window.

“About three years ago, a forensic link at one of the theft sites discovered by a local police agency led us to forensic evidence that linked several of these thefts,” U.S. Attorney Gerard M. Karam said at a news conference, as reported by the Associated Press.

Nicolas Dombek is a fugitive after the government charged him for his alleged role in a 20-year string of museum heists. Photo courtesy of the FBI.

Eight of the nine suspects—Thomas Trotta, Frank Tassiello, Daryl Rinker, Dawn Trotta, Ralph Parry, Damien Boland, Alfred Atsus, and Joseph Atsus—have surrendered to law enforcement, and five have entered guilty pleas. They are all Pennsylvania residents in their mid-to-late 40s and early 50s.

Authorities have declared the ninth man, Nicholas Dombek, a fugitive. They believe he burned the painting Upper Hudson by Jasper Cropsey, stolen from New Jersey’s Ringwood Manor in 2011, leading to additional charges of concealment or disposal of objects of cultural heritage.

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