Algeria and Mali on Tuesday gave differing accounts of an unmanned aircraft that went down in their desert border region.
Algeria's defence ministry said the army shot down an "armed surveillance drone" that violated the country's airspace near Tin Zaouatine, a community that straddles the border.
The ministry did not provide further details.
Neighbouring Mali's army said in its own statement that one of its unmanned aircraft crashed near Tin Zaouatine while on a routine surveillance mission.
It said it had opened an investigation into the incident.
Mali's army has been fighting a jihadist insurgency for 13 years. It is also fighting Tuareg-dominated rebel groups in the north of the Sahel country.
