FIRST ON FOX: ActBlue co-founder Matt DeBergalis pleaded the Fifth Amendment during his closed-door deposition before three key House committees, sources familiar with the matter told Fox News Digital.

The Committee on House Administration, House Oversight Committee, and House Judiciary Committee are conducting a joint investigation into ActBlue, a massive fundraising platform for Democrats, over allegations that lax fraud prevention standards may have allowed foreign donations to seep into U.S. campaigns.

DeBergalis' deposition, which was scheduled for Thursday morning, lasted less than half an hour. He was seen entering and exiting the committee room within roughly 25 minutes.

FAR-LEFT POLITICIANS STILL USING ACTBLUE AS 88-YEAR-OLD DISPUTES DONATING NEARLY $150,000 TO FUNDRAISING GIANT

Employees work at ActBlue in Somerville, Mass., on Nov. 13, 2018. (Jessica Rinaldi/The Boston Globe via Getty Images)

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