WASHINGTON/TEHRAN/JERUSALEM/BEIRUT/LONDON/MELBOURNE/KUWAIT CITY - US forces launched strikes against Iran on Tuesday after the downing of a US Army Apache helicopter a day earlier, the United States Central Command (CENTCOM) said.

The US strikes were "very strong, very powerful," US President Donald Trump told ABC News after the operation began.

The strikes started at 5 pm US Eastern Time (2100 GMT) at the president's direction, CENTCOM wrote on X.

Following the US announcement, Iranian media reported that several explosions were heard early Wednesday and air defense were activated in the port city of Bandar Abbas, Qeshm Island, Sirik county and Jask county in southern Iran.

The semi-official Tasnim news agency reported that six explosions were heard in Sirik, Qeshm Island and the southern city of Minab, adding that areas in the three regions were attacked by US fighter jets.

IRGC responds to US strikes 

In response to the US attacks, Iran's Islamic Revolution Guard Corps (IRGC) said on Wednesday that it launched a drone attack on the US Fifth Fleet in Bahrain.

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The US forces attacked several locations in Jask, Sirik and Qeshm, damaging a telecommunications mast and destroying two water tanks in Sirik, the IRGC said in a statement.

"In the event of continued hostility, heavier responses are on the way," said the statement. 

Kuwait: Air defense systems intercepting enemy targets

Also on Wednesday, the General Staff of the Kuwaiti Army said air defense systems were engaging hostile aerial targets.

The army urged citizens to comply with security and safety instructions and guidelines, and to obtain information from official and approved sources.

Earlier Tuesday, Trump accused Iran of shooting down a US Army helicopter near the Strait of Hormuz and vowed to respond.

"I have just been informed ... that last night the Iranians shot down one of our highly sophisticated Apache helicopters while (it was) patrolling over the Strait of Hormuz," he said in a post on Truth Social.

Two pilots onboard the aircraft "are safe and uninjured," Trump said, adding "Nevertheless, the United States must, of necessity, respond to this attack."

The US strikes came as Israel renewed attacks in southern Lebanon on Tuesday, following days of tit-for-tat strikes between Israel and Iran and adding to already heightened tensions across the region.

Israel says prepared for bigger blow on Iran

In Jerusalem, Israeli military chief Eyal Zamir said on Tuesday that his country's strikes against Iran on Monday were "preparation for a much more significant and forceful blow."

"We are prepared to strike Iran again with another severe and far-reaching blow," Zamir said during a drill in northern Israel, without elaborating.

ALSO READ: Iran's IRGC says targeted 2 Israeli airbases in retaliatory attack

Israel launched airstrikes on Beirut's southern suburbs on Sunday, killing at least two people and wounding some 20 others, according to Lebanese sources.

The strikes triggered a series of mutual attacks between Iran and Israel from Sunday night into Monday, marking the most serious escalation since a ceasefire between Iran, the United States and Israel in April.

Later on Monday, Iran and Israel signaled a halt to their attacks against each other. Still, Israel has warned that it would strike Beirut in response to any attack on northern Israel and continue attacks against Hezbollah in Lebanon, whereas Iran has cautioned that any further Israeli attack on Iran or Lebanon would trigger a much more "severe and crushing" response from Tehran.

Earlier on Tuesday, the Iranian army said two members of its air defense force were killed in the Monday Israeli strikes while defending Iran's airspace.

'16 killed in Israeli airstrikes in S. Lebanon'

In southern Lebanon, at least 16 people were killed and dozens injured in a wave of Israeli airstrikes and drone attacks on Tuesday, according to Lebanon's sources, underscoring the continuing volatility along the Lebanese-Israeli border.

The deadliest attack targeted a residential area in the southern city of Tyre, where eight people were killed and 32 others wounded, according to Lebanon's National News Agency (NNA) and local rescue officials.

Lebanon's Public Health Emergency Operations Center said the cumulative toll from Israeli attacks between March 2 and June 9 had reached 3,666 dead and 11,321 injured.

The Israeli military said it intercepted a rocket fired by Hezbollah at Israeli troops in southern Lebanon on Tuesday night.

The continued violence comes despite a ceasefire agreement reached on June 3 following trilateral negotiations in Washington involving Lebanon, Israel, and the United States.

IMO warning on Hormuz Strait transits

Also on Tuesday, the secretary-general of the International Maritime Organization (IMO) warned against vessels' attempts to transit the Strait of Hormuz without credible security guarantees, stressing that no commercial consideration can justify exposing seafarers to extreme danger.

"I am increasingly concerned by reports that vessels continue to attempt to transit the Strait of Hormuz without any credible security guarantees," IMO Secretary-General Arsenio Dominguez said in a statement.

READ MORE: US forces down 2 Iranian drones that allegedly threatened Hormuz ships

Dominguez said seafarers had already been killed, injured and detained in recent incidents, while the security situation in the region remained highly volatile and lacked reliable assurances for safe navigation.

The IMO chief emphasized that ship masters and shipping companies bear ultimate responsibility for voyage planning and risk assessment under international safety and security management frameworks.

According to IMO figures, as of June 9, a total of 42 maritime incidents had been confirmed since the outbreak of the conflict in late February, resulting in 11 confirmed seafarer fatalities.

Aussie PM says ‘very worried’ about Mideast situation

In Melbourne, Prime Minister Anthony Albanese said on Wednesday that Australia is "very worried" about the human impact of the war in the Middle East after the United States launched new strikes against Iran.

Albanese said that Australia wants to see a de-escalation of the conflict in the Middle East, declaring that a permanent ceasefire would be in everyone's interest.

"We're very worried both about the human impact, of course, that comes with war, but also the economic impact that is having a massive effect on the global economy will get worse rather than better," he told Australian Broadcasting Corporation (ABC) television.