Bernie Sanders' presidential campaign is being punished by the Democratic party for snooping on a rival campaign.

FOX's Jared Halpern has more from Washington:

The Democratic National Committee will not allow Senator Bernie Sanders' campaign to use a DNC voter file after a campaign staffer reviewed private information about Hillary Clinton's campaign.

A spokesman for the Sanders campaign says that staff member has been fired, but blamed a vendor.

The Democratic Party has an extensive list of voter info and rents it out to campaigns to target likely voters and issues.

Firewalls are supposed to prevent campaigns from looking at data from rival campaigns, but a DNC official says the company that runs the system installed a software patch, which briefly allowing access to all data.

In Washington, Jared Halpern, FOX News.