The widening conflict risks drawing in the United States, which has provided crucial military and diplomatic support to Israel, as well as U.S.-allied Arab countries that host American forces.

Israel has been expanding its actions in Lebanon. On Saturday, it made its first strike in the northern city of Tripoli, a Lebanese security official said, and Israeli troops launched raids in the south.

Israeli claims that its soldiers began ground operations inside southern Lebanon "are false," Hezbollah said in a Tuesday statement. "No direct ground clashes have yet taken place between the resistance fighters and the occupation forces," the group said, referring to Israeli troops.