Armed raiders have kidnapped five people working for the French medical NGO Médecins sans frontières (MSF) in the Far North Region of Cameroon.
MSF said that the men entered a building used by MSF in Fotokol near the border with Nigeria and took away the members of their team.
The five comprise three aid workers with Chadian, Senegalese and French-Ivorian nationalities. Two Cameroonian security guards were also abducted, a local administrative official said.
The Far North Region - a tongue of land lying between Nigeria to the west and the marshlands of Lake Chad to the east - has been plagued by attacks on troops and civilians carried out by Boko Haram jihadists and militants from the rival Islamic State West Africa Province (ISWAP).
In September 2019, six Cameroonian soldiers were killed near Fotokol by suspected Boko Haram members.
Last August, 26 Chadians were killed in the marshlands just on the other side of the border.
But the local official cautioned that there was no evidence yet to connect the abductions to jihadist attacks.
"We don't know if it was a simple robbery that went wrong. A safe was opened," he said.
Identity of the kidnappers and motives unclear
"The identity and the motives of those behind it are unclear."
The army has launched a search for the five, said the source, speaking on condition of anonymity.
Violence in the Lake Chad area began with the rise of Boko Haram in Nigeria in 2009.
Since then, more than 36,000 people have died, most of them in Nigeria, and three million have fled their homes, according to UN figures.
The attacks prompted countries in the region in 2015 to set up a joint anti-jihadist mission, the Multinational Mixed Force (MMF), gathering troops from Nigeria, Chad, Cameroon and Niger.
Six MMF troops - four Nigerians and two from Niger - died last December during a sweep in the marshlands in which 22 jihadists were also killed, according to the authorities.
ISWAP emerged in 2016 as a splinter group from Boko Haram amid a dispute over the indiscriminate targeting of Muslim civilians and the use of women suicide bombers.
Boko Haram announced last June that its leader, Abubakar Shekau, had died in fighting with ISWAP.
In addition to jihadist attacks in the north, Cameroon is struggling with an insurgency in the Northwest and Southwest Regions where militants among the country's anglophone minority have launched a campaign for a separate state.
Those groups threatened to disrupt the Africa Cup of Nations football tournament during January and February. But teams and fans were not attacked during the competition.