Updated

U.S. Secretary of State John Kerry says Nigeria must respect human rights as it cracks down on the Islamist extremists. He's also pledging to work hard in the coming months to ease tensions between Sudan and South Sudan.

Kerry is in sub-Saharan Africa for the first time as secretary of state, attending the African Union's 50th anniversary.

He says Nigeria's government is right to fight terrorism, but its forces must not engage in atrocities. U.S. officials say they believe there are continuing abuses occurring in Nigeria's north where President Goodluck Jonathan has declared emergency rule.

Kerry also blamed Sudan's government for much of the tension along its volatile border with South Sudan. He says residents don't want to be subjected to strict Islamist rules.