Terrorists from the Boko Haram group have killed at least 27 people in an attack of “unprecedented savagery” in southeast Niger, local officials said.

Other people were wounded and some more reported missing in the assault on Saturday evening in the village of Toumour in the Diffa region, said a senior local official.

Witnesses and other officials confirmed the attack, which came hours before municipal and regional elections went ahead across the country on Sunday.

“Some victims were killed or wounded by bullets, others were burnt inside their houses, consumed by the flames of an enormous fire set by the attackers,” said the official.

Between 800 and 1,000 houses, the central market and numerous vehicles were also destroyed in the fire, he added.

Roughly 70 attackers arrived at Toumour at around 1745 GMT on foot, having swum across Lake Chad, said the official.

The attack itself lasted three hours, according to AFP.

“They first attacked the residence of the traditional chief, who only just managed to escape,” he said.

“It was an attack of unprecedented savagery,” said a local elected official who asked not to be named. “Nearly 60 percent of the village has been destroyed.”

In November, Boko Haram terrorists killed at least 110 Nigerian civilians, including dozens of farm workers, and injured several others in the volatile northeastern state of Borno, according to the UN. Several women were also kidnapped in the raid.

Also in October, Boko Haram terrorists took the lives of at least 22 farmers working on their irrigation fields near Nigeria’s Maiduguri in two separate incidents.

Northeastern Nigeria has been wracked by years of violence involving clashes between rival communities over land, attacks by heavily-armed criminal gangs, and reprisal killings by vigilante groups.

Boko Haram and the West Africa Province (ISWAP) branch of the Daesh terrorist group have increasingly targeted loggers, herders and fishermen in their violent campaign, accusing them of spying and passing information to the military and the local militia fighting them.

More than 30,000 people have been killed and nearly 3 million displaced in a decade of Boko Haram’s violence in Nigeria, according to the UN Office for the Coordination of Humanitarian Affairs.