Updated

The U.S. Embassy in South Sudan confirms that an American man has been killed in the conflict-torn nation.

South Sudan army spokesman Col. Domic Chol Santo tells The Associated Press the man was killed Saturday morning when opposition rebels attacked the town of Kaya on the Ugandan border.

He says the man was "caught in the fighting" that also left 15 rebels dead.

The opposition says it is looking into the reports.

The man's body is at the military hospital in South Sudan's capital, Juba, until next of kin are notified.

South Sudan's civil war is well into its fourth year, with tens of thousands of people killed.