U.N. High Commissioner for Human Rights spokesman Rupert Colville said there was a deep sense of concern following an April massacre in Nigeria.
The United Nations estimates that about 200 people were killed and more than 2,000 houses were destroyed following a Nigerian military raid in the town of Baga. The raids were allegedly in response to an attack by Islamic militant group Boko Haram, which left one Nigerian soldier dead.
Colville said the Nigerian government was called on to ensure that national security was achieved in a manner that respected human rights. Further efforts are needed to "avoid excessive use of force when conducting operations, as these are feeding local resentment, especially when civilians are killed or have their property damaged," he said.
Boko Haram aims to establish an Islamic state in Nigeria, which is divided along Muslim and Christian lines.
Nigeria President Goodluck Jonathan, a Christian, said he was committed to holding the perpetrators accountable for any violations of the law.
Colville said that last month's attacks was likely the deadliest in the fight against Boko Haram, adding he was "very concerned" by the death toll.