Crude Oil Advances Again

Prolonged refinery outages around the globe and increasing tensions in Nigeria lifted oil prices to a two-month high Monday at the New York Mercantile Exchange.

The July light sweet crude contract advanced 53 cents to $68.53 a barrel late in the session. Reformulated gasoline slipped a penny to $2.26 a gallon. Heating oil was unchanged at $2.02 a gallon.

The near-term natural gas contract fell 18 cents to $7.77 per million British thermal units.

Crude prices reacted sharply to news last week that refinery utilization in the U.S. is well below the average range. The figures have left traders and analysts concerned about U.S. gasoline stores heading into the peak of the summer driving season.

News of a malfunction at Valero's (VLO Quote - Cramer on VLO - Stock Picks) Corpus Christi, Texas, refinery and a restart delay at a Petroleos de Venezuela refinery accentuated the concerns over low refinery utilization figures.

Elsewhere, Nigerian rebels attacked a flow station run by Eni SpA (E Quote - Cramer on E - Stock Picks) on Sunday, taking 12 workers hostage. It isn't yet known which rebel group is responsible for the attack.

Also in Nigeria, a workers union is planning a nationwide general strike beginning Wednesday to protest high gasoline prices. One union leader has said that all oil exports will be halted during the strike, according to Edward Meir, analyst at Man Financial.

Meanwhile, energy stocks were mostly higher. The CBOE Oil Index climbed 0.4% to 777.74. ConocoPhillips (COP Quote - Cramer on COP - Stock Picks) was 0.9% higher at $81.22, and Chevron (CVX Quote - Cramer on CVX - Stock Picks) gained 0.8% to $83.80. Exxon (XOM Quote - Cramer on XOM - Stock Picks) was up fractionally at $86.28.

Hercules Offshore (HERO Quote - Cramer on HERO - Stock Picks) was downgraded by Canaccord Adams to hold from buy, sending its stock 0.6% lower to $35.61.