Thirty-three people have been arrested on suspicion of taking hostages and selling contraband goods in Cameroon's North and Adamawa regions.
Motorbikes and illegal drugs were also confiscated in the operation code-named Adano, the military says.
A spokesman said there had been a recent spike in criminal activity in the northern regions' borders with Nigeria and the Central African Republic (CAR) - including trafficking of various forms and customs fraud.
Cameroon's northern regions have become focal points for kidnappers, with cattle breeders there being the main targets.
In 2018 alone, at least 250 people were kidnapped in Adamawa and North regions, several of them killed by their kidnappers, according to the Association for the Promotion of Animal Husbandry in the Sahel and Savannah.
The kidnapping crisis began in 2013 at the height of CAR's civil conflict.
Rebels from CAR and Chad involved in the war, with the complicity of local criminals, began kidnapping cattle breeders and demanding ransoms.
Some $3.6m (£2.8m) has been paid in ransom between 2015 and 2018, according to several breeders' associations.