TULSA, Okla. (KFOR) – The U.S. Department of Justice announced the takedown of a nationwide catalytic converter theft ring on Wednesday.

According to the Justice Department, searches took place in Oklahoma, California, Wyoming, Minnesota, New Jersey, New York, Nevada, North Carolina, and Virginia.

“Amidst a rise in catalytic converter thefts across the country, the Justice Department has today carried out an operation arresting 21 defendants and executing 32 search warrants in a nation-wide takedown of a multimillion-dollar catalytic converter theft network,” said Attorney General Merrick B. Garland. “We will continue to work alongside our state and local partners to disrupt criminal conspiracies like this one that target the American people.”

Catalytic converters are a part of a car’s exhaust device that lowers the toxic gas and pollutants from a vehicle’s internal combustion engine into safe emissions.

More than 2,000 catalytic converters were stolen in Tulsa in the past year.

“In Tulsa alone, more than 2,000 catalytic converters were stolen in the past year,” said U.S. Attorney Clint Johnson for the Northern District of Oklahoma. “Organized criminal activity, including the large-scale theft of catalytic converters, is costly to victims and too often places citizens and law enforcement in danger. The collective work conducted by federal prosecutors and more than 10 different law enforcement agencies led to the filing of charges in the Northern District of Oklahoma against 13 defendants operating an alleged catalytic converter theft operation.”

A federal grand jury in the Northern District of Oklahoma charged 13 defendants with conspiracy to receive stolen catalytic converters, conspiracy to commit money laundering and other similar charges.