The attack occurred on Sunday when the attackers raided Oke-Ode, a small town around 70 kilometres (45 miles) from the Kwara state capital, Ilorin.
Police said the armed men “invaded” the area, “shooting sporadically”.
Police and forest security services responded and “discovered 12 lifeless bodies” of the guards. Four others were wounded.
It was not immediately clear who the gunmen were.
But gangs known locally as bandits and jihadists operate out of bases hidden in forests across the northern and central states.
The criminal gangs loot and burn down villages as well as carry out kidnapping for ransom.
The state has witnessed a series of deadly attacks in recent months, with locals blaming the Mahmuda group, a gang loyal to Mahmud al-Nigeri, a senior leader of the Ansaru terror group.
Ansaru grew out of a 2021 split within the Boko Haram group and the group then allied itself with Al-Qaeda in the Islamic Maghreb (AQIM).
Nigeria’s national security adviser Nuhu Ribadu said last month that Ansaru has “urban sleeper cells” and “remote forest bases” in Niger and Kwara states in central Nigeria.
In mid-August, Nigerian authorities announced the capture of al-Nigeri along with fellow Ansaru figure Mahmud Muhammad Usman.
Kwara state governor AbdulRahman AbdulRazaq called for “increased security deployments” to help “roll back the activities of criminals”.
tba-sn/kjm
© Agence France-Presse
