U.S. forces in the Middle East shot down dozens of missiles and drones over the weekend as Iran launched its first ever attack from its own territory on Israel, senior White House officials said.

The Iranian attack involved more than 300 aerial munitions, including 100 ballistic missiles, more than 30 cruise missiles and 150 one-way attack drones, senior administration officials said in a telephone press conference Sunday.

The White House believes that 99% of the aerial threats were intercepted and that the attack caused no significant damage, said a senior administration official who was unauthorized to be identified on the record.

U.S. Air Force, Navy and Army assets participated in the operation to shoot down Iranian missiles and drones, which one official called a “spectacular success,” with no American casualties.

Some 70 Iranian drones were shot down by fighter pilots from the 494th Fighter Squadron based out of RAF Lakenheath and the 335th Fighter Squadron from Seymour Johnson Air Force Base, N.C., a senior official said.

The destroyers USS Arleigh Burke and USS Carney in the eastern Mediterranean Sea took down between four and six ballistic missiles, officials said. Meanwhile, an Army Patriot missile battery deployed to Irbil, Iraq, shot down a ballistic missile headed from Iran toward Israel.

Israeli air defense systems were responsible for most of the shootdowns, the administration officials said.

Some of the U.S. units involved were part of a move by Washington over the last week to bring additional aircraft and ships to the region, in anticipation of the attack.

“Thanks to these deployments and the extraordinary skill of our service members, we helped Israel take down nearly all of the incoming drones and missiles,” President Joe Biden said late Saturday in Washington.

The U.S., U.K., France and other countries prepared for two weeks to defend against the weapons strikes, which Iran said would be retribution for Israel killing two of its generals in a strike in Syria at the beginning of April.

Iran and Israel have engaged in a shadow war for many years, but the Hamas-Israel war that began Oct. 7 has brought that conflict into the open. Munitions also were launched from Iraq, Syria and Yemen, where Iranian proxy militias operate.

The White House said that Iran’s intent was to inflict significant damage in Israel. Tehran didn’t give prior warning of the attack, and the scope of the operation is seen as being on the high end of how the administration expected Iran would respond.

As far as what’s next, one senior administration official said the White House would not envision the U.S. participating with Israel in a counteroffensive against Iran.