The stealth bombers that dropped massive bunker-buster bombs on Iranian nuclear facilities have begun returning to a U.S. base in Missouri. An Associated Press journalist watched on a clear but windy Sunday afternoon as at least seven of the B-2 Spirit bombers came in for landing at Whiteman Air Force Base. A first group of four of the stealth aircraft did a loop around the base before approaching a runway from the north. A final group of three arrived within 10 minutes. U.S. officials have said that one B-2 group headed west from the Missouri base on Saturday, intended as a decoy to throw off Iranians. Another flight of seven quietly flew off eastward, ultimately engaging in the Iran mission. The U.S. military struck three sites in Iran Saturday evening, inserting itself into Israel’s effort to destroy Iran's nuclear program in a risky gambit to weaken a longtime foe. The decision to directly involve the U.S. comes after more than a week of strikes by Israel on Iran that have moved to systematically eradicate the country’s air defenses and offensive missile capabilities, while damaging its nuclear enrichment facilities. But U.S. and Israeli officials have said that American stealth bombers and a 30,000-pound (13,600-kilogram) bunker buster bomb they alone can carry offered the best chance of destroying heavily fortified sites connected to the Iranian nuclear program buried deep underground.