Sanders campaign threatens legal action against DNC.

Washington (CNN)Bernie Sanders' campaign on Friday threatened to take the Democratic National Committee to federal court if the party organization doesn't restore access to a crucial voter database.

The internal warfare exploded after the DNC cut off Sanders from the database and said the Vermont senator's presidential campaign exploited a software error to improperly access confidential voter information collected by Hillary Clinton's team.

The revelation poses a setback for Sanders, who is mounting a liberal challenge to the former secretary of state. The DNC database is a goldmine of information about voters and being blocked from it could complicate Sanders' outreach efforts. The timing is also challenging, just weeks before Clinton and Sanders are slated to compete in the Iowa caucuses.

And coming the day before a Democratic debate, the developments fueled a long-held belief in the Sanders camp and among his allies that the DNC has stacked the deck in favor of Clinton.

At a press conference in Washington on Friday, Sanders campaign manager Jeff Weaver accused the DNC of trying to sabotage the campaign and he vowed to fight the DNC in federal court if the campaign's access to the data is not quickly restored.


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