ANKARA, Turkey (AP) — Turkey's president says four soldiers have been killed and around 20 others injured in an explosion at an ammunition depot at a base in southeast Turkey.

The Defense Ministry had announced Friday that 25 soldiers were wounded and seven others were missing following an unexplained accident during the firing of heavy weapons ammunition. The blast occurred at a base in Hakkari province, bordering Iraq and Iran. The base is used to combat Kurdish rebels.

Recep Tayyip Erdogan said Saturday that the incident involved an ammunition depot explosion and resulted in four deaths.

He was speaking at a memorial on the 80th anniversary of the death of the Turkish republic's founder, Mustafa Kemal Ataturk.

It wasn't clear if the explosion occurred during training or a clash against rebels.