Well known militant outfit Boko Haram is being blamed for killing 21 people in separate attacks in a remote northeastern region of Nigeria.
This was suspected by the security officials.
It is believed that the jihadists shot dead 18 forest workers who had been collecting firewood in Borno state.
Eye witnesses said that the bodies were found scattered over several hundred metres and most had sustained injuries to their back or head.
Also on Sunday, a vehicle carrying civilians travelling in a nearby army convoy hit a mine planted by the insurgents.
The explosion killed three people near the village of Wumbi.
The Boko Haram insurgency which broke out in 2009, has killed at least 20,000 people and displaced more than 2.6 million.
The militia has also forced them into camps and host communities.>