Brent and US crude futures both dropped below the range held for most of the past month, in heavy trading that extended losses after the Fed’s statement on Thursday that the world’s top economy faced significant downside risks.

Data showing private sector business activity in Europe and China declined sharply this month added to worries, driving stocks down 4 percent and pummeling commodities as investors headed into safer havens such as the dollar and US government bonds.

“We’re just not seeing any real signs of life out there economically. Traders are heading to higher ground,” said Rob Kurzatkowski, futures analyst with OptionsXpress.

“There is just a lot of doom and gloom out there in the markets.”

Brent crude traded down $4.86 to $105.50 a barrel by 2:39 p.m. EDT (1839 GMT), after dropping to $105.02 a barrel earlier, the lowest level since Aug. 11.

US crude was harder hit, settling down $5.41 at $80.51.

It was the biggest one-day drop in prices since Aug. 8, with prices touching $79.66 a barrel during intraday activity.

Brent trading volumes again eclipsed those of US futures, which have traditionally been the more heavily traded contract.

More than 760,000 Brent contracts had traded by mid-afternoon in New York, the heaviest trading since late June

and 50 percent above the 30-day moving average. US crude trading volumes totaled 705,000 contracts, about 4 percent above that average.

Market players said with traders focusing on wider factors outside of the oil market, such as the euro zone crisis and the economic outlook, Brent was drawing more activity this week.

Brent is viewed as a better benchmark of global conditions, as high volumes of crude from Canada weigh down inventories at the US Midcontinent, where the Cushing, Oklahoma delivery point of the US contract is located.

“The focus on Brent has only intensified with these macro economic developments,” said Joseph Arsenio, managing director at Arsenio Capital Management in Larkspur, California.

“WTI is a contract that doesn’t relate well to most refiners, while Brent does. The prospect of a recessionary

environment relates rather directly to the refiners and therefore to Brent.”

The drop in oil came as part of a wider sell-off in commodities, with benchmark industrial metal copper — viewed

by some as a key indicator of future economic conditions — hitting a one-year low.

The Reuters-Jefferies CRB index, a 19-commodity global benchmark for the asset class, plunged 4.4 percent in

mid-afternoon trading, hitting the lowest level since early December.

Gold, which hit record highs earlier this year as a safe haven amid the economic uncertainty, fell as much as 4.7

percent as investors rushed into the US dollar.