Wasserman Schulz wrote that the suspension will last "until the DNC is provided with a full accounting of whether or not this information was used and the way in which it was disposed."
Sanders staffers temporarily gained access to the information late Thursday due to a software glitch. In a press conference Friday, campaign manager Jeff Weaver accused the DNC of "actively attempting to undermine" Sanders' campaign by blocking its access to voter files. He said the campaign may file a federal lawsuit if the committee continues to block access.
Read the DNC's full statement below:
"Earlier this week, an incident briefly allowed users on the NGP VAN system to inadvertently access some data belonging to other campaigns. During this window, over the course of approximately 45 minutes, staffers of the Bernie Sanders campaign inappropriately accessed voter targeting data belonging to the Hillary Clinton campaign. At no point were financial information, donor records, or volunteer data exposed.
"We consider the security of the NGP VAN system and the integrity of the data it contains a top priority. The error in the VAN software was fixed immediately, and we have been reassured by NGP VAN that the incident did not expose any data to the public or any external entity. This is an isolated incident resulting from a vendor software patch, not a hack, and the users who accessed data were secure users. All VAN data is now secure.
"Upon being made aware of the situation, the DNC immediately directed NGP VAN to conduct a thorough analysis to identify any users who may have accessed data inappropriately and pinpoint exactly what actions any such users took in the system, and to report these findings to the DNC. Further, the DNC has directed NGP VAN to begin a review process of their internal procedures to identify how this mistake was allowed to happen and prevent further such mistakes. In addition to this full and complete internal audit which we have instructed NGP VAN to conduct, we are also beginning the process of securing an independent audit by a data security firm of the company’s procedures.
"Once the DNC became aware that the Sanders campaign had inappropriately and systematically accessed Clinton campaign data, and in doing so violated the agreement that all the presidential campaigns have signed with the DNC, as the agreement provides, we directed NGP VAN to suspend the Sanders campaign's access to the system until the DNC is provided with a full accounting of whether or not this information was used and the way in which it was disposed. I have personally reached out to Senator Sanders to make sure that he is aware of the situation. When we receive this report from the Sanders campaign, we will make a determination on re-enabling the campaign's access to the system.
"We are working with the Sanders and Clinton campaigns and NGP VAN to establish all of the facts and move forward as quickly as possible. Our primary goal at this moment is to ensure the integrity of the data so that the campaigns -- and the entire Democratic Party -- can continue the important work we do of connecting with voters on the issues that matter most to them and their families."