Updated

Oil prices fell slightly to near $86 a barrel Friday in Asia as violent protests in the Middle East keep investors on edge about possible crude supply disruptions.

Benchmark crude for March delivery was down 31 cents at $86.05 a barrel at late afternoon Singapore time in electronic trading on the New York Mercantile Exchange. The contract rose $1.37 to settle at $86.36 on Thursday.

Bahrain's leaders banned public gatherings and sent tanks into the streets Thursday, intensifying a crackdown that killed five anti-government protesters and wounded more than 200. Bahrain is not a major oil-producing country, but it is strategically important to the U.S. as home to the Navy's 5th Fleet.

There have also been anti-government protests in Iran, Algeria, Jordan and Libya following the ouster of regimes in Tunisia and Egypt. Iran is the world's fourth-largest oil producer. Algeria and Libya are also important crude suppliers.

"The rising fears about a huge change in the Middle East region, home to the world's largest oil and gas reserves and production, is providing support to prices," Barclays Capital said in a report.

In London, Brent crude for April delivery gained 17 cents to $102.76 a barrel on the ICE Futures exchange. Traders consider Brent better reflects events in Asia and the Middle East while the traditional benchmark oil, West Texas Intermediary, is currently influenced more by high U.S. crude inventories and sluggish demand.

"The Brent market remains the more important gauge of Asian demand strength and geopolitical risk premium related to evolving civil developments in the Middle East," Ritterbusch and Associates said in a report.

In other Nymex trading in March contracts, heating oil fell 0.4 cent to $2.73 a gallon and gasoline held at $2.52 a gallon. Natural gas futures were down 0.9 cent at $3.86 per 1,000 cubic feet.