Reinforcements arrive as fighting spreads across the region and missile attacks continue
The United States has ordered a major reinforcement of its forces in the Middle East, sending thousands of Marines and a large amphibious assault ship to the region as the war involving Iran enters its second week.
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A U.S. official said about 2,500 Marines from the United States Marine Corps and the amphibious assault ship USS Tripoli have been directed toward the region.
The deployment comes as fighting intensifies between Iran, Israel and their regional allies, raising fears of a wider Middle East conflict.
Marines join growing US military presence
The Marines are part of the 31st Marine Expeditionary Unit, a rapid-response force capable of conducting amphibious landings, evacuating civilians and reinforcing U.S. embassies during crises.
The unit and the Tripoli are normally based in Japan but had already been operating in the Pacific before being redirected toward the Middle East.
Earlier in the week, the United States Navy had about 12 warships operating in the Arabian Sea, including the aircraft carrier USS Abraham Lincoln and several destroyers.
If the Tripoli joins the flotilla, it would become the second-largest ship deployed there after the carrier.
The reinforcement does not necessarily mean a ground invasion is planned. Marine expeditionary units are often used for security missions, humanitarian operations or emergency evacuations.
Explosion at Tehran rally
Meanwhile, tensions inside Iran escalated after a large explosion struck a major demonstration in the capital.
Thousands had gathered at Ferdowsi Square for the annual Quds Day rally, a state-organized event supporting Palestinians and calling for Israel’s destruction.
Footage from the scene showed crowds chanting slogans as smoke rose nearby after the blast. There were no immediate reports of casualties.
Shortly before the explosion, Israeli military accounts issued warnings in Farsi urging people to leave the area. However, many Iranians likely did not see the message because authorities have heavily restricted internet access.
At the rally, Iran’s judiciary chief Gholamhossein Mohseni Ejei was giving an interview on state television when the explosion occurred.
Surrounded by bodyguards, he raised his fist and declared that Iran “under this rain of missiles will never withdraw.”
Thousands of targets struck in Iran
In Washington, U.S. Defense Secretary Pete Hegseth said coalition forces had struck more than 15,000 targets in Iran since the start of the conflict.
Israel also reported hitting over 200 sites in 24 hours, targeting missile launchers, air defense systems and weapons production facilities.
Meanwhile, U.S. President Donald Trump said the war would end “when I feel it in my bones.”
He also warned that Iran’s key oil export terminal on Kharg Island could be attacked if Tehran continues to threaten shipping in the nearby Strait of Hormuz — a crucial waterway that carries roughly 20% of the world’s traded oil.
Iran has already launched missile and drone attacks across the Gulf region and effectively disrupted shipping through the strait.
Rising casualties and regional fallout
Elsewhere in the region, violence continues to spread.
In Lebanon, an Israeli strike on a medical center in the village of Burj Qalaouiyah reportedly killed 12 healthcare workers, according to Lebanese authorities.
Another strike in the coastal city of Sidon killed eight people.
Officials say more than 770 people have been killed in Lebanon since fighting erupted between Israel and the Iranian-backed militant group Hezbollah roughly 10 days ago.
About 850,000 people have been displaced, according to António Guterres, secretary-general of the United Nations.
US aircraft crash adds to losses
The U.S. military also confirmed that all six crew members aboard a Boeing KC‑135 Stratotanker refueling aircraft were killed after the plane crashed in Iraq.
Officials said the crash was not caused by enemy fire. Another aircraft involved in the mission landed safely.
The deaths bring the number of U.S. service members killed during operations related to the conflict to at least 13.
War shows no sign of slowing
As missile attacks, drone strikes and air raids continue across the Middle East, the deployment of additional American forces signals that Washington expects the conflict to persist.
With shipping lanes threatened, oil prices rising and humanitarian crises deepening in neighboring countries, the war is increasingly reshaping security across the region.
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Adapted by ASEAN Now · Source · 13.03 2026