Israel said on Saturday that it had hit military targets inside Iran in response to previous Iranian attacks, again raising fears that the long-running confrontation between the two powerful militaries could escalate into an all-out regional war drawing in the United States.

Israel’s military said it targeted Iran’s missile production sites and air defense systems in what appeared to be a highly calculated response that avoided critical energy infrastructure such as oil fields and nuclear facilities.

Iran appeared to play down the impact of the attack, saying its air defenses had successfully countered the strikes in three provinces – Tehran, Ilam and Khuzestan – and that damage was “limited”.

Iran’s military said early Saturday that two soldiers were killed in the strikes, without clarifying where the deaths occurred. The Iranian soldiers died “facing the projectiles of the Zionist criminal entity”, a reference to Israel, the army said in a statement, which was published in state media.

Meanwhile, the US described the attack as “a self-defense exercise” that “specifically avoided populated areas and focused exclusively on military targets.”

Israel has vowed to make Iran pay for its large-scale rocket attack on October 1, in which about 200 rockets were fired at Israel, forcing people across the country to take cover in bomb shelters. For weeks, Israeli leaders have been deliberating over the nature and scope of such a response.

Here’s what we know.

What happened?

In the early hours of Saturday local time, Israel launched direct airstrikes against Iran, carrying out what it said were “precision strikes on military targets”.

Israel’s military said its air force struck “missile production facilities” it said were used to make the missiles Iran has fired at Israel over the past year.

It also said the Israeli military struck “surface-to-air missile arrays and additional Iranian air capabilities that were intended to restrict Israel’s freedom of air operation in Iran.” It is unclear whether those production facilities also produced missiles launched by Iranian proxies Hezbollah, Hamas and Yemen’s Houthi rebels.

Iran later confirmed the attack but said the strikes caused only “limited damage” in some areas, while images on state media showed calm on the streets of the capital Tehran.

Iran’s state news agency reported that the strikes targeting “military centers in Tehran, Khuzestan and Ilam provinces” were “successfully intercepted”.

Several explosions were heard west of Tehran around 2:15 a.m. local time (7 p.m. ET Friday), according to the state news agency. Iranian officials said the explosions heard across the country were related to the installation of air defense systems.

The initial strikes were closely followed by a second wave, as video posted on social media by Tehran residents showed fire and explosions lighting up the Iranian capital’s sky as dawn approached. A third and final wave then followed.

At around 6am local time, the Israeli military said it had ended its operation, saying the “mission was accomplished” and that the Israeli planes “returned home safely”.

How did we get here?

Saturday’s strikes are part of Israel’s long-awaited retaliation Iran’s missile attack earlier this month, as the ongoing war in the Middle East continues to escalate to dangerous new levels.

On October 1, Iran fired 200 projectiles at Tel Aviv and Israeli military bases in what it said was a response to the killing of Hezbollah leader Hassan Nasrallah and others, the largest attack of its kind ever.

That missile barrage came about 24 hours after Israel launched a ground war in Lebanon, opening a new front in its war against Iran-backed militants.

Israel and Iran have been waging a shadow war through proxies and covert actions for decades. In April, that war came to a head when Iran launched a barrage of drones and missiles at Israel in a unprecedented attack in response to an alleged Israeli attack on the Iranian consulate in Damascus, Syria.

In recent weeks, Israel has stepped up its attacks against Iran’s proxies, including launching strikes against the Houthis in Yemen and militants in Syria.

But Israel refocused its operations in Lebanon after cross-border attacks escalated after Israel eliminated the leadership of Iran-backed Hezbollah in a series of assassinations and airstrikes.

Hezbollah leader Nasrallah was killed in an Israeli strike on his underground compound in Beirut in September. Netanyahu previously said his killing was a “necessary step” toward changing the “balance of power in the region for years to come.”

Israel’s war in Lebanon has killed more than 2,500 people, displaced 1.2 million and created a unprecedented humanitarian crisis, according to Lebanon’s leader and international health officials.

In a statement issued at the start of Saturday’s actions, the Israeli military accused Iran and its regional proxies of relentlessly attacking Israel, starting with an October 7 attack by Iran-allied Hamas that killed more than 1,200 Israelis and another 250 kidnapped.

Following the October 7 attacks, Israel declared war on Hamas and launched military operations in Gaza that killed more than 42,000 people.

UN human rights chief warned on Friday that “one of the darkest moments” of the war is unfolding in the north from Gaza, where the Israeli army “subjects an entire population to bombing, siege and starvation”.

What happens next?

A major concern of the escalating military escalations is that Israel and Iran will be embroiled in a full-scale war, one that risks drawing the US — Israel’s closest ally and largest arms supplier — into the fray.

A senior US administration official said President Biden had “encouraged” Netanyahu last week to “engineer” a retaliatory strike that would “deter future attacks against Israel”.

In recent weeks, the US and other allies have urged Netanyahu to exercise restraint and avoid striking Iran’s nuclear and oil assets.

US allies in the Gulf, including the United Arab Emirates, Bahrain and Qatar, have expressed similar concerns as an attack on Iranian oil facilities could create negative economic and environmental impacts for the entire region, an Arab diplomat said. CNN said.

The White House said the US “did not participate in this operation” and called on “Iran to cease attacks on Israel so that this cycle of fighting can end without further escalation.”

By refraining from attacking Iran’s oil or nuclear sites, Israel has left room for possible de-escalation. But it is unclear whether Iran will respond to this latest attack.

Israel’s top military spokesman, Rear Admiral Daniel Hagari, said after the attacks ended that if Iran began “a new round of escalation,” Israel would be “forced to respond.”

CNN’s Mostafa Salem, Alex Marquardt, Jeremy Diamond, Lauren Izso, Artemis Moshtaghian, Eugenia Yosef, Matthew Chance, Nechirvan Mando, Zeena Saifi, Alex Stambaugh, Samantha Waldenberg, Kayla Tausche, Paul P. Murphy, Isaac Yee, Avery Schmitz, Hamdi Alkhshali and Tara John contributed reporting.

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