Fifteen military and 3 bystanding civilians were killed in the blast in Mahjeh, northern countryside of Daraa, according to local media.
The Syrian state-run television said the incident was an explosion in a mine depot belonging to terrorist groups, while some other media said the blast occurred when the Army forces were trying to defuse mines left by the terrorists.
The Syrian forces took control of the entire Daraa Province, southern Syria, ten days ago.
The war waged by terrorists in Syria is backed by some states, including Saudi Arabia, United Arab Emirates, the US and the Zionist regime of Israel.
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