The Syrian Civil Defense group known as the White Helmets claims that the Syrian military deliberately targeted them with airstrikes in the Hama Province, saying a strike hit their base of operations in Kafr Zita, while a second strike hit the same site later, killing rescuers on scene.
Such double-tap strikes are a common way of both discouraging rescue attempts when a military wounds someone they don’t want being saved, and of adding to the number of casualties by killing presumptive allies of the initially wounded.
Unfortunately this all too often also ends up causing large civilian death tolls when an airstrike hits a group of civilians or other apparently random bystanders, and rescue groups show up on the scene to try to save them only to become targets themselves.
The White Helmets operate exclusive in rebel-held parts of Syria, and that has many times put them in the line of fire. Though the Syrian government has denied deliberately targeting them in the past, the frequency with which they come under fire raises serious doubts about that.