Nigerian officials say at least 87 people have been killed in an attack by the Boko Haram militant group in the northeastern state of Borno.

“Eighty-seven bodies were recovered in the bush and our people are still searching for more,” Saidu Yakubu of the Environmental Protection Agency in the state.

The attack took place late Tuesday in the town of Benisheik, lies 70 kilometers (45 miles) west of the state capital, Maiduguri, by members of the group disguised in military fatigues.

Witnesses say the militants opened fire on people trying to flee the town while setting people’s houses on fire.

Following the attack, Borno state governor Kashim Shettima went to Benisheik and visited the scene, describing the killings as “barbaric.”

In May 2013, the Nigerian government imposed a state of emergency in three states in the northeast, saying Boko Haram had become a security threat in those states.

Boko Haram says its aim is to topple the Nigerian government, which it accuses of being pro-Western.

The group has claimed responsibility for a number of deadly gun and bomb attacks in various parts of Nigeria since 2009.

Over the past four years, violence in the north of Africa's most populous country has claimed the lives of 3,600 people, including killings by the security forces.