WASHINGTON (AP) -Bernie Sanders campaign manager says DNC is “actively attempting to undermine” campaign.

A summary of computer logs show that four aides to Vermont Sen. Bernie Sanders’ presidential campaign accessed proprietary voter data compiled by the campaign of rival Hillary Clinton.

And the records also show that the aides conducted 25 separate searches of voter information and some saved the results.

That’s according to a person familiar with the data logs and the breach. The person spoke on condition of anonymity because they were not authorized to speak publicly.

The person says the data represents millions of dollars of Clinton campaign investment.

The database of voters is maintained by a vendor for the Democratic National Committee, which has temporarily barred Sanders’ campaign from accessing it.

Sanders’ campaign has fired its national data director and planned to hold a news conference on Friday afternoon.