Syrian army shows C-4 explosives in the Yarmouk Basin in the southern province of Daraa, June 1, 2019. The Syrian army on Saturday showed to media outlets a large amount of C-4 explosives they found in the southern province of Daraa. An estimated four tons of C-4 explosives were found in the Yarmouk Basin area in the countryside of Daraa, the army said, adding the rebels hid the explosives ahead of their defeat in the province last year. (Xinhua/Ammar Safarjalani)

Photo taken on June 1, 2019 shows C-4 explosives in the Yarmouk Basin in the southern province of Daraa. The Syrian army on Saturday showed to media outlets a large amount of C-4 explosives they found in the southern province of Daraa. An estimated four tons of C-4 explosives were found in the Yarmouk Basin area in the countryside of Daraa, the army said, adding the rebels hid the explosives ahead of their defeat in the province last year. (Xinhua/Ammar Safarjalani)

Syrian army shows C-4 explosives in the Yarmouk Basin in the southern province of Daraa, June 1, 2019. The Syrian army on Saturday showed to media outlets a large amount of C-4 explosives they found in the southern province of Daraa. An estimated four tons of C-4 explosives were found in the Yarmouk Basin area in the countryside of Daraa, the army said, adding the rebels hid the explosives ahead of their defeat in the province last year. (Xinhua/Ammar Safarjalani)

C-4 explosives are shown in the Yarmouk Basin in the southern province of Daraa, June 1, 2019. The Syrian army on Saturday showed to media outlets a large amount of C-4 explosives they found in the southern province of Daraa. An estimated four tons of C-4 explosives were found in the Yarmouk Basin area in the countryside of Daraa, the army said, adding the rebels hid the explosives ahead of their defeat in the province last year. (Xinhua/Ammar Safarjalani)

Syrian army shows C-4 explosives in the Yarmouk Basin in the southern province of Daraa, June 1, 2019. The Syrian army on Saturday showed to media outlets a large amount of C-4 explosives they found in the southern province of Daraa. An estimated four tons of C-4 explosives were found in the Yarmouk Basin area in the countryside of Daraa, the army said, adding the rebels hid the explosives ahead of their defeat in the province last year. (Xinhua/Ammar Safarjalani)

Syrian army shows C-4 explosives in the Yarmouk Basin in the southern province of Daraa, June 1, 2019. The Syrian army on Saturday showed to media outlets a large amount of C-4 explosives they found in the southern province of Daraa. An estimated four tons of C-4 explosives were found in the Yarmouk Basin area in the countryside of Daraa, the army said, adding the rebels hid the explosives ahead of their defeat in the province last year. (Xinhua/Ammar Safarjalani)