Energy Contracts End Mixed

Meanwhile, the Chinese central bank's overnight increase of its benchmark lending rate was partly responsible for the softness earlier. The Chinese government's effort to gradually slow its economy could result in a decline in global demand for crude oil, according to analysts.

Elsewhere, violence escalated in Nigeria over the weekend when rebel groups abducted three factory workers from the Anambra region. Nigerian troops raided several villages in search of rebels and weapons near the country's main oil distribution center of Port Harcourt.

Among the stocks in the news, Royal Dutch Shell (RDS.A Quote) has begun repairing its breached Nembe Creek pipeline. Security fears were preventing technicians from entering the area since the rupture occurred on March 4.

Generally, energy stocks finished the trading session higher. The iPath Goldman Sachs Crude Oil (OIL Quote) ETF was ahead by 0.7% at $35.56.

ConocoPhillips (COP Quote) climbed 0.47%, Chevron (CVX Quote) advanced 1.9%, and ExxonMobil (XOM Quote) was up 1.8%.

E&P firm Mariner Energy (ME Quote) was upgraded by Calyon Securities to buy from add. Its stock traded 2.7% higher at $17.40.

Kodiak Oil & Gas (KOG Quote) rose 0.8% to $4.89 after it reported a loss of 4 cents a share for 2006.

Hercules Offshore (HERO Quote) announced that it is acquiring the drilling services firm Todco (THE Quote) in a cash and stock deal worth $2.3 billion. Shares of Hercules ware off 4.7% at $25.32, but Todco traded 19.7% higher at $39.24.