As if the residents of Hawaii’s Big Island don’t have enough to worry about already, the US Geological Survey is now warning residents of yet another threat: large rocks shooting from Kilauea’s crater. Several rocks, including one measuring two feet wide, have already fallen— but the situation could get even worse.

It’s been two weeks since Hawaii’s Kilauea volcano began erupting, and there’s no apparent end in sight. At least 17 fissures have been recorded in the volcano’s East Rift Zone, and ash plumes from the crater are raising the possibility of acid rain and volcanic smog, or “vog,” packed with noxious sulfur dioxide. The US Geological Survey (USGS) is warning that the eruption is still evolving and additional outbreaks of lava are possible, along with ongoing ground deformations and earthquakes.