The Islamic State West Africa Province (ISWAP), a Boko Haram offshoot, claimed responsibility for a deadly attack this week on a state governor’s election motorcade in Nigeria that may have involved some beheadings days before people in the African country head to the polls on Saturday.

“There was heavy fighting between the attackers and the soldiers and CJTF [Civilian Joint Task Force],” a member of the civilian force told the Agence France-Presse (AFP) news agency on condition of anonymity.

Although core Islamic State (ISIS/ISIL) in Iraq and Syria accepted Boko Haram’s pledge of allegiance in 2015, ISWAP broke away from the Nigeria-based terrorist group in 2016 over leadership differences, prompting some in the U.S. government to treat the groups as separate entities.

On Wednesday, the pro-ISIS Amaq news agency claimed responsibility for the attack on behalf of ISWAP, claiming the terrorist group had killed 42 people in Tuesday’s attack on the election convoy of the governor of Borno state, the birthplace of Boko Haram.

Reuters, however, learned from unnamed Nigerian officials that “between three and ten people were killed, and that some of them may have been beheaded,” later explaining:

Security sources said earlier on Wednesday the gunmen opened fire at the motorcade transporting Borno’s state governor Kashim Shettima [from the ruling All Progressives Congress (APC) party] on his way from state capital Maiduguri to the market town of Gamboru for a rally. Two security sources said three people died. A government and a separate security source said as many as ten people were killed. Some of those killed may have been beheaded, they said.

Gov. Shettima survived, but some other victims are also missing, Deutsche Welle (DW) reported.

The terrorists kidnapped APC supporters and took them into the bush, AFP learned.

“We still don’t know the fate of several of our supporters who were abducted during the fight,” Ngari Kalla, an APC campaigner, reportedly declared.

“There vehicle was stuck and before they could get out the gunmen surrounded them and took them away. This is a major concern to us,” Kalla added.

Last month, the U.S. Embassy in Nigeria issued a security alert for American citizens, warning that Boko Haram and its offshoot ISWAP are planning to “disrupt” the elections.

Soon after, Nigerian President Muhammadu Buhari’s administration accused members of the opposition of mobilizing the jihadis to disrupt the general elections with “massive attacks” in several states.

Over 84 million Nigerians are expected to go to the polls on February 16 to elect the nation’s president and members of the lawmaking National Assembly.

“The incumbent governor [of Borno]— at the end of a maximum two four-year terms — was campaigning for a seat in Nigeria’s Senate in Nigeria’s elections due to take place on Saturday. Muslim-majority northeast Nigeria, including Borno, is an APC stronghold,” Reuters noted.

The opposition has blasted the Buhari administration’s record on combating ISIS and Boko Haram.

As it repeated the false allegation it has made on various occasions of having “successfully defeated” Boko Haram, the Buhari administration claimed last week that Nigeria is now facing a new “global insurgency,” referring to ISWAP.

Last week, Gen. Thomas Waldhauser, the top U.S. commander in Africa, told American lawmakers, “ISIS West Africa has grown. … They’re now in the neighborhood probably of around 3 to 4,000 [jihadis] … They now have taken large pieces of real estate in northern Nigeria.”

Referring to ISWAP, he added, “They’re the one that we have the most concern about because we are not sure what their intentions would be with regards to outside the region. Boko Haram probably [has] around a thousand [fighters].”