Boko Haram captured two buses on Sunday in Nigeria and Cameroon, leaving at least seven people dead. The attacks come right after Nigeria delayed presidential elections due to safety concerns in the northeast region.

The jihadists captured one bus with thirty people in Bouba Kaina, about 11 miles from the Nigerian border. AFP reports the group executed twelve people, but the Associated Press claims only seven died.

Chetima Ahmidou, a principal of a school in the area, said Boko Haram members took eight young girls hostage. His brother was the bus driver and one of the murdered civilians.

Boko Haram drove the bus towards Nigeria. The group also hijacked a bus in Akada-Banga in Nigeria. Officials claim they kidnapped over twenty people, including many women and children.

Also on Sunday, Boko Haram attacked Diffa, Niger, on the border with Nigeria. The army pushed Boko Haram back but, some hours later, a bomb exploded in a market, which killed five people. Militants then stormed a prison in Niger overnight on Sunday, but officials did not reveal if the attack killed or wounded everyone.

On Monday, Niger’s parliament “unanimously approved sending troops to northern Nigeria” just hours after the prison attack. The country will send 750 soldiers to their neighbor to fight the radical Islamic group.

Niger, Nigeria, Cameroon, Chad, and Benin agreed on “a joint force of 8,700 troops” to defeat the radical Islamic group. “The pooling of the efforts and resources of concerned countries will contribute without doubt to crushing this group which shows scorn, through its barbaric acts, for the Muslim religion,” said Niger’s parliamentary speaker Adamou Salifou.

Locals in Diffa knew Boko Haram jihadists had escaped to Niger with Nigerian civilians who attempted to escape the attacks. Under the guise of refugees, the terrorists established sleeper cells to infiltrate Niger.

“Most of the Boko Haram fighters who have operated in Diffa have come from these displaced,” an officer told Reuters. “They are Nigerian refugees or people from Niger who had been in Nigeria. There are real networks.”

Officials reported Diffa was quiet on Tuesday morning. “The situation in Diffa is very serious,” promised Niger Defense Minister Karidio Mahamadou. “We will do everything to protect the population. We will wage war against Boko Haram all the way to its last hideout.”

Nigerian officials rescheduled the election from February 14 to March 28 “after security chiefs pleaded more time to make voting safe in parts of the country seized by Boko Haram.”

In five years, the radical Islamic group murdered thousands and displaced over 1.6 million people. “If the security of personnel, voters, election observers and election materials cannot be guaranteed, the lives of innocent young men and women and the prospect of free, fair and credible elections will be greatly jeopardized,” said Professor Attahiru Jega, chairman of the Independent National Electoral Commission (INEC).