Niger has begun air surveillance operations along its northern border with Libya to monitor possible infiltration of armed groups fleeing the conflict in the neighbouring country, Niger military sources said.
The air patrols started after authorities said they had seized nearly 60 vehicles and a dismantled helicopter smuggled out of Libya last week, underscoring the threat of the conflict spilling over into weakly controlled neighbours to the south.
Authorities in the region are concerned some forces in Libya's conflict, including Gaddafi's loyalists and mercenaries from Niger and Mali fighting there, could cross the largely unpatrolled Sahel region into their territory.
Libyan rebel fighters have entered the capital Tripoli in a coordinated move that has routed forces loyal to leader Muammar Gaddafi.
"We are closely watching the developments in Libya and in that context, we have ongoing aerial observation operations over the region of Agadez so as to be ready to deal with any infiltration," an officer of the West African nation's military intelligence said late on Sunday, requesting not to be named.
Niger's government was unreachable for comments.
Another military source said authorities were concerned the fighting could reach the southern Libyan city of Sebha, pushing Gaddafi loyalists towards Niger, while criminals could see an opportunity to get their hands on abandoned heavy weapons.
Governments of the region that includes Mali and Mauritania believe fighters of al Qaeda in the Islamic Maghreb (AQIM) have received convoys of weapons including SA-7 missiles plundered from Gaddafi's abandoned arms caches.
Niger authorities say the Agadez region has become a central point of smuggled weapons and other goods looted from Libya.
Last week, police said they seized 60 unmarked vehicles and a dismantled helicopter which most probably came from Libya.
"For the helicopter, I can say that it was already dismantled when it arrived here, but I do not know if it is still operational, or if they are just parts of a downed aircraft that has been recovered," a custom official said.