) -- Crude oil futures tumbled nearly 5% Friday morning, as fears over Dubai's debt roiled U.S. commodities markets.

Global investors began scurrying to safety after

Dubai said late Wednesday that a state-controlled investment entity requested a six-month abeyance on repayments for $60 billion in debt. U.S. investors returned to a shaky, abbreviated Friday trading session following Thursday's Thanksgiving holiday.

The January delivery contract for crude oil plunged below $73 earlier, as news from the emirate undercut recent optimism about economic recovery. Crude oil futures recently slipped $3.70 to $74.26 a barrel.

The pullback in crude oil futures also were weighed by geopolitical concerns in the Middle East, where a standoff between the International Atomic Energy Agency and Iran intensified. The governing body of the IAEA voted to censure Iran on Friday for building a secret uranium enrichment site.

Energy equities fell, in turn, after the opening bell, as most major integrated operations laid mired in red.

Dow Jones Industrial Average


Exxon Mobil

(XOM) - Get Report



(CVX) - Get Report

slid 1.9% and 2.3%, respectively.

Servicers also slumped, as the Philadelphia Oil Service Sector Index dropped 3.6%.


(HAL) - Get Report


BJ Services



Baker Hughes (BHI)

shed 4.1%, 3.5% and 3.8%, respectively.

The dollar, too, strengthened against a basket of currencies, with the Dollar Index recently higher by 0.7%.

Elsewhere on the NYMEX, the January delivery contract for heating oil lost 8 cents to about $1.96 a gallon. Natural gas futures for January delivery declined by 17 cents to $4.99. The January delivery contract for gasoline also fell 9 cents to $1.93 a gallon.

-- Written by Sung Moss in New York