By Oren Liebermann, Natasha Bertrand and Haley Britzky, CNN

(CNN) — The US carried out a round of strikes in Yemen against the Iran-backed Houthis on Wednesday evening, according to Defense Secretary Lloyd Austin, targeting five underground weapons storage facilities using B-2 stealth bombers.

The facilities housed advanced conventional weapons used to target military and civilian vessels in the Red Sea and the Gulf of Aden, three US defense officials told CNN following the attack.

“This was a unique demonstration of the United States’ ability to target facilities that our adversaries seek to keep out of reach, no matter how deeply buried underground, hardened, or fortified,” Austin said in a statement. “The employment of US Air Force B-2 Spirit long-range stealth bombers demonstrates U.S. global strike capabilities to take action against these targets when necessary, anytime, anywhere.”

It marked the first time the US has used the strategic stealth bomber to attack the Houthis in Yemen since the beginning of the US campaign. The B-2 is a much larger platform than the fighter jets that have been used so far to target Houthi facilities and weapons, capable of carrying a far heavier load of bombs.

Austin said he authorized the strikes at the direction of President Joe Biden in order to “further degrade” the Houthis’ abilities after more than a year of attacks by the militant group on US and international vessels in the region. The facilities attacked were holding “various weapons components” of weapons used to target vessels in the Middle East, the defense secretary said.

“We will continue to make clear to the Houthis that there will be consequences for their illegal and reckless attacks,” he said.

The night-time airstrikes hit Yemen’s capital city of Sanaa and the city of Saada early on Thursday local time, Houthi-run Al Masirah TV reported, according to Reuters.

“America will pay the price for its aggression on Yemen, and as we have said before, its aggression will not deter Yemen from its stance in support of Gaza,” Nasruddin Amer, the deputy head of the media office for the Houthis, said on X.

The Houthis have for months targeted ships in the Red Sea, one of the world’s busiest waterways, calling the attacks a response to Israel’s war in Gaza against Hamas.

Hamas, Hezbollah and the Houthis are all part of an Iran-led alliance spanning Yemen, Syria, Gaza and Iraq that has attacked Israel and its allies since the war began. They say they won’t stop striking Israel and its allies until a ceasefire is reached in the Palestinian enclave.

The attack on the Houthis comes at a time of great tension in the region. Israel is expected to retaliate for Iran’s recent missile barrage before the November 5 US election, and its conflicts with Hezbollah in Lebanon and Hamas in Gaza are ongoing.

Wednesday’s strike — early Thursday morning, local time — is the latest in a saga of back-and-forth attacks by the Houthis and the US, as the Houthis have been carrying out constant attacks on commercial shipping and Navy assets in the region for months.

It also comes as US service members have begun arriving in Israel after the US announced the deployment of an advanced anti-missile system to help protect Israel following Iran’s missile barrage.

While the US has in the past carried out strikes against the Houthis in partnership with the UK, Wednesday’s strike was carried out by the US alone. According to US Central Command, both US Air Force and Navy assets were involved in the operation.

Over the past year, the US has repeatedly struck or intercepted Houthi drones and missiles in an effort to protect ships and degrade the Houthi arsenal.

In September, the Houthis claimed to have launched approximately two dozen ballistic and cruise missiles and drones against three US destroyers. Deputy Pentagon press secretary Sabrina Singh said “at no time” did any of the cruise missiles or drones hit a US ship.

“I can confirm that no US ships were damaged or hit. There was no injuries to US personnel. We did see a complex attack launch from the Houthis that range from cruise missiles and UAVs,” Singh said. “My understanding is that those were either engaged and shot down or failed.”

Just earlier this month, the US struck 15 Houthi targets in Yemen, including “Houthi offensive military capabilities,” CENTCOM said.

In September, the Houthis fired a missile deep inside Israel though, Israel’s military assessed that it “most likely fragmented in mid-air” and fell into an open area in the country, resulting in no injuries.

Israeli Prime Minister Benjamin Netanyahu said in September that the Houthis would pay a “heavy price” for the attack. Just days later, the Israel Defense Forces said it targeted power plants and a seaport in airstrikes against the Houthis.

The Houthis have since launched more attacks against Israel, saying they launched drones on October 1 in support of Hezbollah, and that they fired two missiles and multiple drones into the country on October 7.

The Israeli military said on the latter attack, Israel had intercepted a surface-to-air missile fired from Yemen toward central Israel.

The Houthis’ constant attacks on commercial shipping have killed multiple mariners and resulted in major environmental issues. In August, an attack on a Greek-flagged vessel left it on fire and leaking oil; the Pentagon warned at the time of a “potential environmental catastrophe.”

The US has significant firepower in the region, and it has since Hamas’ invasion of Israel last October. CNN reported this month that the thousands of US forces included a carrier strike group, several additional guided missile destroyers, an amphibious ready group along with a marine expeditionary unit, and a broad range of aircraft including fighter and attack aircraft.