Nigerian security forces are denying reports soldiers killed at least 30 people and burned shops and houses in the city of Maiduguri in revenge for a bomb attack.
Residents of the northeastern city say soldiers went on a rampage Monday after a bomb went off near an army patrol, killing at least one soldier.
A statement from Nigeria's Joint Task Force on Wednesday denied those accounts, saying there is "no recorded case of extra-judicial killings, torture, arson and arbitrary arrests by the JTF in Borno state."
The JTF is fighting the militant group known as Boko Haram, which is based in Maiduguri, the Borno state capital. Witnesses have accused the security force of brutal tactics and human-rights abuses.
A politician from nearby Kano state, speaking on condition of anonymity, said the secrecy around Boko Haram frustrates efforts to isolate or subdue the group.
"They do not wear a tag, they do not wear a T-shirt that proclaims they are Boko Haram," said the politician. "So, all you do is talk to the younger elements in your family to be aware of these people. They should not join any group; they should watch their movement, just moral persuasion."
Much about the group remains unclear, but the militants are believed to want to impose a strict form of Islamic law across northern Nigeria. It is blamed for killing more than 1,000 people in northern and central Nigeria since 2010.