The sources, who include Ghanaian security officials and regional diplomats, said Ghanaian authorities appeared to be mostly turning a blind eye to the insurgents crossing over from neighbouring Burkina Faso to stock up on food, fuel and even explosives, as well as getting injured fighters treated in hospital.
But they said that approach, while so far sparing Ghana from the kind of deadly Islamist attacks that have plagued its neighbours, risks allowing militants to put down roots in the country and recruit in some marginalised local communities.
Ghana shares a 600 km (372 mile) border with Burkina Faso, the country at the heart of an insurgency that has killed thousands, displaced millions and, according to some experts, turned the Sahel region into the epicentre of global terrorism as factions loyal to al Qaeda and Islamic State expand their presence.
Burkina Faso has lost control of over half its territory as a pro-al Qaeda group known as JNIM gained ground.