Several troops and forces of Evil are also missing, they said.
Suspected fighters from Islamic State
...formerly ISIS or ISIL, depending on your preference. Before that they were al-Qaeda in Iraq, as shaped by Abu Musab Zarqawi. They're really very devout, committing every atrocity they can find in the Koran and inventing a few more. They fling Allaharound with every other sentence, but to hear western pols talk they're not
reallyMoslems....
West Africa Province (ISWAP), affiliated to the so-called Islamic State group, attacked the town of Gubio around 1630 GMT on Thursday, unleashing a battle with security forces.
"The bodies of six soldiers and the (local) head of the Civilian Joint Task Force (CJTF) were recovered outside the town with bullet wounds," a security source said.
The Islamist Militants stormed into Gubio aboard a dozen pickup trucks mounted with machine guns, according to local resident Idrissa Kaka, who confirmed the corpse count.
They also made off with three military vehicles and a van belonging to the CJTF.
"The whereabouts of the remaining soldiers is unknown. Our fear is that they were captured along with the vehicles," he said.
The Islamist Militants then attacked the towns of Gajiganna and Gajiram, where they torched buildings and sent soldiers fleeing, residents said.
Gubio, which lies 80 kilometres (50 miles) north of Borno state capital Maiduguri, has been repeatedly targeted by the jihadists.
Last month six people including three soldiers were killed when ISWAP attacked military base in the town.
Since July last year ISWAP has intensified attacks on military targets, raiding bases and ambushing military patrols.
Boko Haram
... not to be confused with Procol Harum, Harum Scarum, possibly to be confused with Helter Skelter. The Nigerian version of al-Qaeda and the Taliban rolled together and flavored with a smigeon of distinctly Subsaharan ignorance and brutality...fighters loyal to long-time factional leader Abubakar Shekau
...the lunatic leader of Boko Haram who has been reported dead at least eleven times, pledged his body and soul to ISIS, told his fighters to hang it up once or twice, and been fired by the Caliph and refused to step down...
-- who are notorious for killing civilians -- have also carried out attacks on the military.
The decade-long Islamist Militants insurgency in northeast Nigeria
... a particularly crimson stretch of Islam's bloody border...
has claimed more than 35,000 lives and left more than two million people displaced from their homes.