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In response to U.S. attacks, Iran targeted several countries across the Gulf, including Bahrain, Kuwait, Qatar, Jordan and Oman.-/AFP/Getty Images

The U.S. military said it has launched another round of strikes against Iran “to degrade their ability to attack commercial ships freely transiting the Strait of Hormuz.”

The strikes, which took place overnight and into early Monday in Iran, came after attacks by the military on Sunday morning in response to an Iranian strike on a container ship in the critical waterway the day before.

Iran responded with attacks on Bahrain, Kuwait, Qatar, Jordan and Oman – the nation on the other side of the strait that Tehran has pressed to collaborate in managing shipping traffic.

The U.S. struck again later in the day. The Governor of Qeshm Island near the strait told Iran’s state-run IRNA news agency that projectiles were fired at military targets, with no casualties. Explosions were also heard in the coastal city of Bandar Abbas and Hajiabad city to the north.

A U.S. official said a few strikes were conducted on missile and air defence systems and paramilitary Revolutionary Guard boats at a couple of locations to further degrade Iran’s ability to attack commercial shipping. They spoke on condition of anonymity because they were not authorized to publicly discuss military operations,

Iran and the U.S. are nearly at the midway point of the 60-day period of their interim deal aimed at reaching a permanent end to the war. The strait, a key route for the global supply of oil and natural gas and long considered an international waterway, has become a sticking point in negotiations that seem in danger of collapse.

“A return to full-scale hostilities would have catastrophic consequences,” United Nations Secretary-General António Guterres said, according to a statement.

Iran says the strait is closed but the U.S. disagrees

The U.S. military earlier Sunday said it hit some 140 targets, including missile and drone launch sites, ammunition dumps, communication equipment and other sites.

The attacks were heavier than in recent days. The U.S. has launched three rounds of air strikes targeting Iran in the past week over attacks on ships heading through the strait using a route off Oman, seeking to avoid the Islamic Republic’s territorial waters.

Opinion: Trump sincerely wants to wash his hands of the Iran war. But he doesn’t have the cards

“We bombed the hell out of them last night,” U.S. President Donald Trump told NBC’s “Meet the Press.”

Semi-official Iranian news agencies reported that a navy officer was killed. Iran retaliated by attacking nations in the region hosting U.S. military forces, while insisting it alone must control the strait and potentially charge vessels for travelling through it.

“The era of one-sided deals is OVER,” Mohammad Bagher Qalibaf, the speaker of Iran’s parliament and a main negotiator, wrote. “We told you: keep your word or pay the price. Reality is knocking.”

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A man holds a poster of the late Iranian Supreme Leader Ayatollah Ali Khamenei in a gathering commemorating him at a square in Tehran, on Saturday.Vahid Salemi/The Associated Press

Iran said the strait was closed until calm is restored, and Tehran would consider targeting “additional enemy bases in the region” if it faced more attacks. The U.S. military and Trump asserted that the strait remained open.

The U.S. military said over 140 ships had transited over the past week. A multinational body overseen by the U.S. Navy said traffic continued “at reduced levels” off both Oman and Iran, and that nearly 140 vessels transited daily before the war.

About a fifth of all traded oil and natural gas passed through the strait before the war. Iran’s grip on it led to a global energy crisis, though oil prices have sharply dropped since wartime highs of US$120 a barrel.

Oman summons Iranian envoy to protest attack

Missile alerts sounded across several Gulf Arab countries.

Qatar’s military said it intercepted incoming Iranian fire, with explosions heard in the neighbouring United Arab Emirates. Three people, including a child, were wounded by shrapnel from the interception of attacks, Qatar’s Interior Ministry said.

Missile alerts sounded in Bahrain, home to the U.S. Navy’s 5th Fleet.

Kuwait’s Defence Ministry said three “land border posts” in the north and an offshore drilling platform of the Kuwait Oil Company were damaged, with one worker wounded.

Sirens sounded in Kuwait as the country's air defences engaged to intercept incoming fire after the United States launched airstrikes targeting Iran.

The Associated Press

Three Iranian missiles struck areas across Jordan, causing minor damage but no injuries, Jordan’s state news agency reported.

The Omani state news agency said drones struck sites in an area on the waterway, a day after Oman and Iran held talks on the strait and agreed to continue discussions. The strait sits in Iran and Oman’s territorial waters.

Oman summoned the Iranian ambassador to protest the strikes, the first such move since the war began, calling Iran’s acts “irresponsible.”

Iranian strike on ship harms Indian crew

The Cyprus-flagged container ship hit by Iran suffered “significant engine room damage,” the U.S. military said.

Oman’s maritime authority said it rescued 23 crew members but one was missing. India’s foreign ministry called him an Indian national.

The United Kingdom Maritime Trade Operations centre, overseen by the British military, said the ship had been moving along Oman’s shoreline.

Crowds call for revenge during funeral for Iran’s late Supreme Leader Ayatollah Ali Khamenei

Iran’s Revolutionary Guard said multiple vessels “disregarded our warnings” and ignored instructions to follow what it called an approved route. One “was struck by a warning shot and brought to a stop.”

Iranian state media later reported U.S. strikes across the country, including southern Iran in the province closest to the strait and military sites in a province near Tehran.

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An Iranian woman rides a motorcycle next to a banner with a picture of the late Supreme Leader of Iran, Ayatollah Ali Khamenei, on a street in Tehran, on Saturday.Majid Asgaripour/Reuters

Attacks followed more diplomatic talks about the strait

Trump suggested last week that the interim deal in the war was “over.” But mediators, including Pakistan, Qatar and Egypt, have continued efforts to reach an agreement.

A regional official involved in mediation, speaking on condition of anonymity to discuss talks, said efforts to shore up the ceasefire continued Sunday. Pakistan said its foreign minister spoke by phone with Iran’s top diplomat and urged “de-escalation” on both sides.

Iran’s new supreme leader, Ayatollah Mojtaba Khamenei, unseen since the war began, on Saturday vowed in his first statement since the funeral of his father, Ayatollah Ali Khamenei, that Iranians would avenge his killing in the war’s opening strikes on Feb. 28.

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