WASHINGTON -- Special counsel Robert Mueller's team is worried that Russian intelligence services will use a criminal case in Washington to gather information about its investigation.

Prosecutors are asking a federal judge to impose limits on the information that can be shared by attorneys for Concord Management and Consulting LLC. The company is accused of funding a clandestine Russian social media operation aimed at interfering in the 2016 U.S. presidential election.

Mueller's team says disclosure of the information could compromise American sources and methods for monitoring foreign interference operations.

Prosecutors also want to bar other defendants from accessing the materials turned over in the case until they appear in a U.S. court. That includes Yevgeny Prigozhin, a wealthy businessman who controls the company. He has ties to Russian President Vladimir Putin.