Roof knocking

Roof knocking (Hebrew: הקש בגג; Arabic: صاروخ تحذيري) or "knock on the roof" is a term used by the Israel Defense Forces (IDF) to describe its practice of dropping low-yield devices on the roofs of targeted civilian homes in the occupied Palestinian territories as a prior warning of imminent bombing attacks to give the inhabitants time to flee the attack. The practice was employed by the IDF during the 2008–2009 Gaza War, the 2012 Gaza War, the 2014 Gaza War, and the since 2023 ongoing Gaza War to attack a variety of targets.

The application of roof knocking is often argued to only have legal reasons rather than the intention to reduce civilian casualties. The impact of the smaller device often puts the civilian population in a state of shock, making them unable to flee the larger attack which often follows only 45 to 180 seconds later. According to the IDF, this period must be very short as otherwise the intended target could flee too, however, in practice the period proves to be too short for civilians to flee. Civilian casualties after a "knock on the roof" are often considered human shields by Israel, without differentiating between voluntary and involuntary human shields.