As part of its effort to bring Hamas down once and for all, Israel has started pumping seawater into the tunnels that lie underneath Gaza, according to several reports. The Wall Street Journal, which first published the news, paints the effort as a "move to flood the tunnels with water from the Mediterranean," and says initial tests have already been performed—though it also acknowledges the plan is "in an early stage" and that its utility "is still being evaluated." CNN's report sounds a bit more tempered; the network says Israel recently informed the US it has started "carefully testing" the flooding of some tunnels "on a limited basis." ABC News also cited sources who said limited flooding had taken place so far. Flooding the entire tunnel system, which is used by Hamas and includes thick blast doors, could take weeks, and analysts say a variety of techniques will need to be used to completely destroy it.
Israel's interest in flooding the 300 miles worth of labyrinthine tunnels has been reported previously, and concerns have been raised about the environmental impacts (Egypt flooded a section of the tunnels with seawater in 2015, leading to tainted water supplies and damages to crops and homes) as well as possible impacts to Israeli hostages—Hamas still holds more than 100 of them, and some believe the terrorist group may be keeping some hostages in the tunnels. Asked about the reports of Israel flooding the tunnels at a Washington, DC, press conference Tuesday, US President Joe Biden said, per Reuters: "With regard to the flooding of the tunnels. I'm not at lib—, well. There (are) assertions being made that ... there's no hostages in any of these tunnels. But I don't know that for a fact." (More Israel-Hamas war stories.)