(Bloomberg) -- Turkey President Recep Tayyip Erdogan said four soldiers were killed and about 20 soldiers injured in a blast at a military base in Hakkari province that authorities have said was probably accidental.

Faulty ammunition is believed to have caused explosion at the installation, and “an investigation has started into the accident,” the Turkish Defense Ministry said Friday in a statement.

The province, in Turkey’s southeast along the border with Iraq and Iran, has been the site since 1984 of clashes between the country’s army and fighters from the Kurdish separatist group PKK, including a roadside bombing blamed on the militants that killed four soldiers in October 2017.

In his televised speech on Saturday in which he gave the blast’s casualty count, Erdogan outlined the country’s “efforts against terrorism,” and said Turkey will “bring peace and security soon” to the eastern Euphrates region of northern Syria, where other ethnic Kurdish militias backed by the U.S. are operating.

To contact the reporter on this story: Baris Balci in Istanbul at bbalci4@bloomberg.net

To contact the editors responsible for this story: Benjamin Harvey at bharvey11@bloomberg.net, ;Steve Geimann at sgeimann@bloomberg.net, Tom Lavell

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