When Israel bombed buildings outside the southern Lebanese city of Sidon, Mohamed Arkadan and his team rushed to an emergency unlike anything they had ever seen. About a dozen apartments had collapsed onto the hillside they once overlooked,

Israeli officials notified the U.S. that it planned to begin a ground incursion into Lebanon that would be limited in scope, scale and duration, and two U.S. officials tell NBC News that the operation appears to have begun.

According to two U.S. officials, Israeli ground forces have begun the process of crossing the border into southern Lebanon. The officials said the U.S. does not have independent confirmation, but the timing tracks with what the Israelis notified the U.