U.S.-launched Tomahawk cruise missiles destroyed three coastal radar sites in Houthi-controlled territory on Yemen’s Red Sea Coast early Thursday, officials said, a retaliatory action that followed two incidents this week in which missiles were fired at U.S. Navy ships.

The strikes marked the first shots fired by the U.S. in anger against the Houthis in Yemen’s long-running civil war. The U.S. previously only provided logistical support and refueling to the Saudi-led coalition battling Yemen’s Shiite rebels known as Houthis and their allies, including supporters of Yemen’s former president, Ali Abdullah Saleh.

While the U.S. military has been focused on al-Qaida in Yemen, the Houthis had not been a primary target of American forces until the missile launches from Houthi-controlled territory this week.

No information on casualties from the U.S. missiles was provided by American officials. The three radar sites were in remote areas, where there was little risk of civilian casualties or collateral damage, said a military official who was not authorized to be named and spoke on condition of anonymity.

The destroyer USS Nitze launched the cruise missiles, the official said.

President Barack Obama authorized the strikes at the recommendation of Defense Secretary Ash Carter and the chairman of the Joint Chiefs of Staff, Gen. Joseph Dunford, Pentagon press secretary Peter Cook said in a statement. U.S. officials had said earlier that the U.S. was weighing what military response to take.

“These limited self-defense strikes were conducted to protect our personnel, our ships and our freedom of navigation in this important maritime passageway,” Cook said following the U.S. action. “The United States will respond to any further threat to our ships and commercial traffic, as appropriate, and will continue to maintain our freedom of navigation in the Red Sea, the Bab al-Mandeb and elsewhere around the world.”

In a sign of the regional nature of the Yemen conflict, the Houthis’ ally Iran announced Thursday that it was deploying two warships into the Bab el-Mandeb strait and the Gulf of Aden.

The semi-official Tasnim news agency said the deployment of the Alvand and the Bushehr was part of a regular anti-piracy patrol off Yemen and East Africa. Still, its announcement hours after the American strike appeared aimed at sending a signal to the United States.

Iran says it supports the Houthis, though it denies arming the rebels. The U.S. Navy says it has intercepted shipments of weapons from Iran bound for Yemen.

Meanwhile, Yemen’s state news agency Saba— under Houthis’ control— quoted an unnamed military official as saying that US accusations that a US destroyer had come under attack from areas under control of Houthis were false. He said, “all these claims are totally untrue and that the popular committees (Houthi militias) have nothing to do with such action.”

He added, “such claims are part of the general context of creating false justifications to escalate assaults and cover up the continuous crimes committed by the aggression against the Yemeni people, along with the blockade imposed on it, and after the increasing condemnations to such barbaric and hideous crimes against Yemenis.”

Loai al-Shami, a Houthi spokesman, had earlier declined to comment on the U.S. strike.

Sharaf loqman, spokesman for the Yemeni army, called it an “American farce to find a reason to interfere in Yemen directly after failure of the Saudis.”

He said that the army never targets ships outside the territorial waters and only those that enter the Yemeni waters come under attack.

Early Wednesday, two missiles were fired at the USS Mason, an Arleigh Burke class of guided missile destroyer that is conducting routine operations in the region with the USS Ponce, an amphibious warship. Neither missile got near the ship, said a U.S. military official.

The missiles were fired from the Yemen coast, near the location used Sunday when two missiles were launched at the same two ships, said the official, who was not authorized to be named and spoke on condition of anonymity.

A second official said it wasn’t clear whether the ship’s countermeasures caused the missiles to hit the water on Wednesday or if they would have landed there anyway. The official also spoke on condition of anonymity.

“These unjustified attacks are serious, but they will not deter us from our mission,” the chief of naval operations, Adm. John Richardson, said in a statement Wednesday. “The team in USS Mason demonstrated initiative and toughness as they defended themselves and others against these unfounded attacks over the weekend and again today. All Americans should be proud of them.”

Col. Walid Zeyad, a top naval official in Hodeida, told the AP that radars were in three different sites: Ras Eissa and Khoukha (both in Hodeida) and al-Makha port, of the western province of Taiz. He said that they were hit early morning around 7 a.m.

The area is a hub of weapons smuggling. The general impression in Yemen was that since the Saudi imposition of a blockade, and the air campaign, all radars were destroyed. When asked Zeyad if these radars are new, he declined to comment.

The missiles fired on Sunday were variants of the so-called Silkworm missile, and both also fell harmlessly into the water. The Silkworm is a type of coastal defense cruise missile that Iran has been known to use.

Sunday was the first time that U.S. ships were targeted by a missile launch from Yemen. Last week, an Emirati-leased Swift boat came under rocket fire near the same area and sustained serious damage. The United Arab Emirates described the vessel as carrying humanitarian aid and having a crew of civilians, while the Houthis called the boat a warship.

The U.S. has been considering withdrawing its support for the Saudi-led coalition fighting the Houthis following Saturday’s airstrike on a funeral and other troubling incidents of civilian casualties as a result of the Saudi bombing campaign.

The strike on the funeral in the capital, Sanaa, killed some 140 people and wounded more than 600. That bombing, among the deadliest of the war, likely sparked the rebels to launch more ballistic missiles in Saudi Arabia and target the U.S. warships in the Red Sea.

Human rights groups have expressed outrage over the deaths and accused the U.S. of complicity, leading the White House to say it was conducting a “review” to ensure U.S. cooperation with longtime partner Saudi Arabia is in line with “U.S. principles, values and interests.”

Meanwhile, an international human rights group, Human Rights Watch, said Thursday that the funeral bombing constitutes an apparent war crime and that the remnants of missiles found at the site of the attack showed that they were American-made. It said a disproportionate number of the victims were civilians when the coalition carried out two airstrikes.

An international investigation is needed into the “atrocity,” said Sarah Leah Whitson, Middle East director for the rights group. She said the attack on the funeral joins a long list of abuses by the coalition.

The U.S. missile launch also could affect relations with Iran, which says it backs the Yemeni rebels but denies arming them. That’s contradicted by the U.S. Navy, which says it has intercepted several shipping boats since the war began carrying Iranian weaponry suspected to be on the way to Yemen.

There was no immediate reaction to the U.S. launch Thursday morning in Iran, which was marking the Shiite commemoration of Ashoura. Houthi-linked media also did not report the strike.

The missile fire by the Houthi raises questions about maritime safety in the Bab el-Mandeb Strait, which serves as a gateway for oil tankers headed to Europe through the Suez Canal. The U.S. moved more naval ships near the strait after an Emirati-leased Swift boat came under rocket fire near the same area and sustained serious damage. The United Arab Emirates described the vessel as carrying humanitarian aid and having a crew of civilians, while the Houthis called the boat a warship.

Analysts with the Washington Institute for Near East Policy called the Houthi missile fire “a surprisingly aggressive move,” but stressed there were limits to Iran’s control of the rebels.

“Houthi relations with the Islamic Republic resemble the Iran-Hamas relationship more than the Iran-Hezbollah relationship — that is, the Houthis are autonomous partners who usually act in accordance with their own interests, though often with smuggled Iranian arms and other indirect help,” the analysts wrote in a report released early Thursday.

(AP)