In the last week of June alone, incendiary devices launched from the Gaza Strip started nearly 100 fires in Israel. Such devices, often created from balloons, have destroyed thousands of acres of forest and farmland. After visiting communities in southern Israel most affected by these attacks, and seeing both the weapons and the damage they cause firsthand, Matthew Aiesi concludes that they are violations of the laws of war:
These fire balloons are cheap, simple to mass-produce, and effective in their design and destructiveness. They consist of a bomblet made of a small bag holding an accelerant-soaked roll of gauze (or other absorbent material), connected to a homemade fuse and tied with a string to a balloon (or a condom used as a balloon). The natural and constant breeze off the Mediterranean Sea, which blows from Gaza to Israel, carries these incendiary devices into the civilian communities in Israel, some just a few-hundred meters (or less) away from the border with Gaza. The fuse eventually burns the string that connects the bomblet to the balloon, dropping the bag and remainder of the fuse to start a fire wherever it lands. Not all the fuses stay lit, and sometimes the balloons deflate or get caught in trees. Sometimes they land harmlessly on concrete, but at other times they damage or destroy buildings or acres of farmland, and they can require significant resources to extinguish.
As Hamas has been using them, these incendiary balloon attacks violate numerous rules and customs of warfare—principally concerning the targeting of civilians and the use of indiscriminate weapons. . . . [T]he Israeli communities in the Gaza envelope are purely civilian communities, surrounded by agricultural land. There are no static IDF bases or outposts in the area—certainly not within range of these devices.
By promising to end these attacks [in its negotiations with Israel], Hamas, the de-facto authority in Gaza, demonstrated that it had both knowledge of, and effective control over, the individuals making the incendiary weapons and illegally attacking civilians. This makes the attacks attributable to Hamas and not mere Palestinian civilians or protestors.
Read more on Lawfare: https://www.lawfareblog.com/incendiary-balloons-national-security-lawyers-witness-war-crimes