Crude oil futures plunged 12 percent on Wednesday - its most in seven years - after a report revealed U.S. supplies of crude, gasoline and distillate fuels rocketed as demand declined.

Supplies of crude oil rose as much as 6.68 million barrels to 325.4 million barrels last week, surpassing the forecast of 800,000 barrels made by analysts, according to a Bloomberg survey.

Crude futures for February delivery slumped $ 5.84 or 12 percent to $42.74 a barrel by 2:30 p.m. in the New York Mercantile Exchange. Earlier in the day prices fell more than $6.

Worries Russia's cut in gas supplies to Europe through Ukraine and a dismal job report affected prices.

Gasoline inventories rose 3.33 million barrels to 211.4 million barrels. The forecast had been for a rise of only 1 million barrels. Distillate supplies, including heating oil and diesel surpassed the 1.1 million gain forecasted, climbing 1.79 million barrels to 137.8 million.

Brent Crude for delivery in February went down $4.53, or 9 percent, to $46 a barrel on the London's ICE Futures Europe exchange Wednesday.