Hillary Clinton’s presidential campaign released a statement on Friday afternoon calling for a swift investigation into the breach of its voter data by members of opponent Sen. Bernie Sanders’ (I-VT) staff.

Brian Fallon, Hillary for America’s national press secretary, wrote that the campaign was “informed that our proprietary data was breached by Sanders campaign staff in 25 searches by four different accounts and that this data was saved into the Sanders’ campaign account.”

“We are asking that the Sanders campaign and the DNC work expeditiously to ensure that our data is not in the Sanders campaign’s account and that the Sanders campaign only have access to their own data,” he continued.

Fallon was much more candid on Twitter, where he said the Sanders staffers who viewed the voter data may have gotten “a pat on the back.” Sanders’ data director, Josh Uretsky, was fired for looking at the Clinton campaign’s information.