A Syrian boy receives treatment at a hospital in the regime-held part of Aleppo on October 13, 2016. Syrian state television said four children were killed by rebel rocket fire on a school in a western regime-held neighbourhood. (Photo by George Ourfalian/AFP Photo)

Akram Abu al-Foz places a painted empty shell on top of a Christmas tree he decorated from empty shells he collected in the rebel held besieged city of Douma, in the eastern Damascus suburb of Ghouta, Syria December 23, 2016. (Photo by Bassam Khabieh/Reuters)

A Turkey-backed Syrian fighter fires a rocket-propelled grenade as he takes part in a military exercise in the countryside of the northwestern city of Afrin, in rebel-held part of Aleppo province, on May 31, 2022. (Photo by Rami al Sayed/AFP Photo)

Volodymyr, a service member of the Ukrainian armed forces, plays with puppies at fighting positions on the line of separation from pro-Russian rebels in Donetsk region, Ukraine on April 10, 2021. The two unnamed puppies living on frontline positions will be taken home and named by soldiers departing on troops rotation. (Photo by Oleksandr Klymenko/Reuters)

Muhannad al-Kadiri (R),18, and Ibrahim Eid, 16, demonstrate their Parkour skills over a military vehicle in the rebel-held city of Inkhil, west of Deraa, Syria, February 4, 2017. (Photo by Alaa Al-Faqir/Reuters)

Armed Yemeni children sit in the back of a pick up truck with fighters loyal to Yemen's Saudi-backed President Abedrabbo Mansour Hadi in the Dar saad neighbourhood of the southern Yemeni city of Aden on May 10, 2015, as they continue to battle Shiite Huthi rebels. (Photo by Saleh Al-Obeidi/AFP Photo)

Leidi, a member of the 51st Front of the Revolutionary Armed Forces of Colombia (FARC), poses for a picture at a camp in Cordillera Oriental, Colombia, August 16, 2016. A peace deal will end half a century of war and allow the rebels to reintegrate into Colombian society. (Photo by John Vizcaino/Reuters)

This Wednesday, August 31, 2016 photo, provided by the Syrian anti-government activist group Aleppo Media Center (AMC), shows Syrian boys dive into a hole filled with water that was caused by a missile attack in the rebel-held neighborhood of Sheikh Saeed in Aleppo province, Syria. (Photo by Aleppo Media Center via AP Photo)