Nigerian extremist group Boko Haram Monday claimed responsibility for an attack on a village in neighboring Niger, which left 27 people dead.

A number of others were wounded and missing in the attack, which occurred Saturday night in Tumur, Diffa region, according to a senior local official.

Witnesses and officials confirmed the attack, which came on the eve of municipal and regional elections across Niger Sunday.

"We want to inform the world that we are responsible for the attack in the town of Diffa in the Republic of Niger yesterday," a three-minute video sent to Agence France-Presse said.

The video showed a fighter in military clothing with a turban, speaking the Hausa language widely used in the area.

"We carried out the attack with the strength and help of God," he said.

The group, led by leader Abu Bakr Al-Shakawi, whose whereabouts are unknown, has vowed more attacks on Christians.

Local officials said that some victims in Diffa were shot dead and others burned inside their homes.

Between 800 and 1,000 homes, as well as the central market and several vehicles were destroyed in a fire set by the rebels, they said.

Dozens of the attackers arrived at Toumour Serra in the evening, after they swam across Lake Chad, an official said. The attack lasted three hours.

"They attacked first the headquarters of the local official, who managed to escape," he added.

"It was an attack with unprecedented brutality," said another official, who asked not to be identified. "Nearly 60 percent of the village has been destroyed."

Boko Haram began its insurgency in 2009 in northeastern Nigeria, before spreading to neighboring countries, including Niger, Cameroon and Chad.

Since then, more than 36,000 people have been killed in Nigeria and two million have been forced to leave their homes, causing a humanitarian crisis in the region.

A regional military coalition was formed to combat the insurgency.