The risk of an expanded Iran war ​grew as Yemen’s Iran-aligned Houthis on Saturday launched their first attacks on Israel since the start of the conflict, as additional U.S. forces reached the Middle East.

Washington has dispatched thousands ‌of Marines to the Middle East in the month-old war. The first of two contingents arrived on Friday on an amphibious assault ship, the U.S. military said on Saturday.

The Washington Post reported on Saturday that U.S. officials said the Pentagon was preparing for weeks of ground operations in Iran, possibly involving raids by Special Operations and conventional infantry troops. Whether President Donald Trump would approve plans for deploying ground troops remained uncertain, the Post reported.

Reuters has reported that the Pentagon was considering military operations that ​could include deploying ground troops in Iran.