The United States and Iran exchanged strikes aimed at infrastructure and military targets on Saturday as their battle over the Strait of Hormuz intensified. The region has endured days of back-and-forth attacks in a conflict increasingly focused on control of the strait, an essential waterway that used to carry a fifth of the world’s crude oil. The collapse of an interim ceasefire leaves no clear end in sight for the war that the US and Israel began more than four months ago.

The US Central Command said on Saturday that its seventh straight night of strikes had hit “surveillance sites, military logistics infrastructure, underground weapons storage, and maritime capabilities.”