Oil fell $2 a barrel to plumb new five-year lows on Friday after the world's energy watchdog forecast even lower prices on weaker demand and higher supplies next year.
Benchmark Brent oil tumbled to below $62 a barrel and U.S. crude slumped to under $58 to extend Thursday's landmark fall below $60.
Surging crude inventories in the United States and top oil exporter Saudi Arabia's reiteration that it will not cut production had roiled prices over the past two days despite data pointing to strong U.S. economic recovery.
On Friday, the Paris-based International Energy Agency which coordinates the energy policies of industrialized countries, cut its outlook for demand growth in 2015, triggering another collapse.
The IEA slashed its outlook for global oil demand growth for 2015 by 230,000 barrels per day to 900,000 bpd on expectations of lower fuel consumption in Russia and other oil-exporting countries.
It predicted that oil-producing nations outside of the Organization of the Petroleum Exporting Countries will add to global supplies. It also expected prices to fall further.
"That's just more bad news for the oil markets," said Andrew Lipow, president of Houston-based Lipow Oil Associates.
"Without any bullish news in sight, this market is going to continue to sell off. I myself will be on the sidelines until I see some supply disruptions occurring or more significant cuts in drilling investments or idling of rigs. People tried to pick a bottom at $80, $70, $60 and they lost a lot of money."
Brent <LCOc1> was down $1.86 at $61.82 per barrel by 12:18 p.m. EST,after falling to $61.35, its lowest since July 2009.
U.S. crude <CLc1> was down $2 at $57.95 per barrel, after touching a bottom at $57.34, its weakest since May 2009.
Brent was headed for a near 11 percent loss on the week and U.S. crude about 13 percent. In dollar terms, both markets were down more than $8 a barrel on the week.
Both markets have lost almost half of their value since June, when Brent stood at above $115 and U.S. crude around $107.
"We're getting to the point where major support for the market might be at $50," said John Kilduff, partner at New York energy hedge fund Again Capital. "Of course, we'll a few more hurdles before that, but that seems to be where we're headed."
(By Barani Krishnan; Additional reporting by Simon Falush in London and Adam Rose in Beijing; Editing by Marguerita Choy)