They were kidnapped on Wednesday, October 30 by unknown individuals between Ngouboua and Chukutalia, two localities in the region of Lake Chad

They were returning from a tour and were intercepted by kidnappers who probably took them off.
The 4×4 vehicle that was transporting the three men was found abandoned on the way from Ngouboua to Chuktalia, we are on the northern shores of Lake Chad. According to preliminary reports, the vehicle, which was carrying the Baga Sola District Chief Medical Officer, a nurse, and the driver, who was being intercepted by armed men who probably carried them on dugout canoes off Lake Chad.Chad

The same sources recall that the Islamist group Boko Haram has training camps on the many islands of Lake Chad where the hostages could have been taken away.
According to several analysts, this is the first time the Islamist group has done what looks like a hostage-taking of civilian health personnel.
Usually, they kidnap girls and women after their operations. The Boko Haram wing led by Abu Mousab El Barnawi who controls the Nigerian shores of Lake Chad breaks new ground in the operative world, says one observer.