The five, one of whom was an officer, were killed on Monday night in the village of Sagme, close to the Nigerian border and the Lake Chad region, according to relatives and local sources. Three other soldiers were wounded.
No one has claimed responsibility for the killings but the area has seen many incursions by the Nigerian jihadist group Boko Haram in the past.
The Cameroonian army has not commented.
Cameroon, along with Chad and Niger, has joined a military effort by Nigeria to crush Boko Haram, a militant movement opposed to Western influence and seeking an Islamic state based on Sharia law, but the countries have increasingly seen the conflict spread across their borders.
Since 2014, the group has killed 2,000 civilians and soldiers and kidnapped about 1,000 people in northern Cameroon, according to an analysis by the International Crisis Group (ICG) think tank.
Boko Haram has caused the deaths of at least 20,000 people since it took up arms in 2009.
In December, a report by the UN Committee against Torture denounced "serious crimes and atrocities" by Boko Haram in Cameroon but also said it had great concern over reports of abuse by Cameroonian security forces.
AFP
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