The U.N. peacekeeping mission said one of its helicopters was in the air during the 8:30 a.m. attack on Bentiu, the Unity state capital.

CNN: SHARE THIS

When some 50, 000 displaced people arrived last month in Bentiu, the oil town where Talisman is based, it was able to fly in emergency help.

ECONOMIST: Sudan��s oil

In a statement, South Sudan Information Minister Banaba Marial Benjamin said that three bombs had struck a market in Bentiu, killing two civilians, including a 12-year-old boy.

CNN: SHARE THIS

The BBC's James Copnall, recently in Bentiu, says that while the conflict has not spread beyond a limited geographical area, talk of a slide towards war is not far from the truth.

BBC: South Sudan's Salva Kiir says Sudan has declared war