Caterpillar says it believes that a search warrant executed by federal authorities on Thursday at its facilities concerns "export filings" related to its Switzerland subsidiary CSARL.

Federal agents appeared Thursday at three Caterpillar facilities near Peoria, Illinois, where the company is headquartered.

Caterpillar spokeswoman Corrie Heck Scott confirmed to NBC Chicago that "Caterpillar is cooperating" with law enforcement but did not provide further details.

In a statement Thursday, Caterpillar, one of the largest construction equipment manufacturers in the world, says the issue it concerns was first disclosed in a 2015 filing with the Securities and Exchange Commission.

At that time, Caterpillar said the SEC had notified the manufacturer that it was conducting an informal investigation relating to CSARL, and asked the company to preserve relevant documents.

Sharon Paul, a spokeswoman for the U.S. Attorney's office for the Central District of Illinois also confirmed its presence at the facilities, but declined to comment on what the search was being conducted for.

Paul said the agencies involved included the Internal Revenue Service's criminal investigation unit, the U.S. Department of Commerce Office of Export Enforcement and the Federal Deposit Insurance Corp.'s office of inspector general. She declined to comment further.

Video obtained by NBC affiliate WEEK, showed agents wearing IRS jackets at the company's main headquarters.

In January, Caterpillar Inc. announced it was moving its global headquarters to the Chicago area. The company previously planned to build a new headquarters complex in downtown Peoria, but those plans have since been canceled.

Caterpillar has faced a number of investigations in recent years focusing on its business practices, according to filings with the Securities and Exchange Commission.

Most recently, in early 2015, a federal court in Illinois subpoenaed the company for documents and information relating to the distribution of profits and movement of cash among its subsidiaries. It's not clear if that matter has been settled or if it is related to Thursday's search.

In 2014, the SEC subpoenaed Caterpillar seeking information about the company's accounting related to its acquisition of Bucyrus International in 2011. It's not clear if that investigation is ongoing or completed.

In 2013 and 2014, Caterpillar subsidiary Progress Rail was the target of two investigations into environmental and other violations, at least one of which was settled with a California agency. Also in 2014, two other subsidiaries were under investigation for anticompetitive bid practices in Brazil and criminal charges were brought against three employees of those subsidiaries.

Check back for details on this developing story.