The Associated Press / Residents and officers from Israel’s Home Front Command on Friday inspect a house destroyed by an Iranian missile strike in Zarzir, northern Israel.

DUBAI, United Arab Emirates — The American military has ordered 2,500 Marines and an amphibious assault ship to the Middle East, a U.S. official said Friday, in a major addition of forces in the region after nearly two weeks of war with Iran.

Hours later, President Donald Trump said U.S. forces had “obliterated” military targets on Iran’s Kharg Island — the primary terminal that handles Iran’s oil exports — and warned that the island’s oil infrastructure there could be next.

Meanwhile in the Iranian capital, a large explosion rocked a central square where thousands were gathered for an annual state-organized rally to support the Palestinians and call for Israel’s demise. Israel had warned that it would target the area in central Tehran.

There were no reports of casualties. But the decision to proceed with the mass demonstration attended by some senior government officials, and Israel’s threat to target the area, underscored the fierce determination on both sides in a war that has rattled the global economy and shows no sign of letting up.

Iran has continued to launch widespread missile and drone attacks on Israel and neighboring Gulf states, and has effectively closed the Strait of Hormuz, through which a fifth of the world’s traded oil passes, even as U.S. and Israeli warplanes pummel military and other targets across Iran.

The humanitarian crisis in Lebanon deepened, with nearly 800 people killed and 850,000 displaced as Israel launched waves of strikes against Iran-backed Hezbollah militants and warned there would be no let up.

In an interview with Fox News, Trump said the war would end “when I feel it in my bones.” He was also more measured about the prospect of opponents toppling the Islamic government.

“So I really think that’s a big hurdle to climb for people that don’t have weapons,” Trump said, citing Iran’s paramilitary Basij force, which has played a central role in crushing recent nationwide protests.

Marines, assault ship will add to US forces

Elements from the 31st Marine Expeditionary Unit and the amphibious assault ship USS Tripoli have been ordered to the Middle East, according to the U.S. official, who spoke to The Associated Press on condition of anonymity to discuss sensitive military plans.

Marine Expeditionary Units are able to conduct amphibious landings, but they also specialize in bolstering security at embassies, evacuating civilians and disaster relief. The deployment does not necessarily indicate that a ground operation is imminent or will take place.

The new Marine deployment was first reported by The Wall Street Journal.

The 31st Marine Expeditionary Unit, as well the Tripoli and other amphibious assault ships carrying the Marines, are based in Japan and have been in the Pacific Ocean for several days, according to images released by the military. The Tripoli was spotted by commercial satellites sailing alone near Taiwan, putting it more than a week away from the waters off Iran.

Earlier in the week, the Navy had 12 ships, including the aircraft carrier USS Abraham Lincoln and eight destroyers, operating in the Arabian Sea. Should the Tripoli join this flotilla, it would be the second-largest ship behind the Lincoln in the region.

While the total number of U.S. service members on the ground in the Middle East is not clear, Al-Udeid Air Base alone, one of the largest in the region, typically houses some 8,000 U.S. troops.

US strikes Persian Gulf island

The U.S. strikes on Iran’s Kharg Island in the Persian Gulf targeted military sites but left alone its oil infrastructure for now, Trump said in a social media post.

But he warned that if Iran or anyone else interferes with the passage of ships through the Strait of Hormuz, he will reconsider his decision not to “wipe out the Oil Infrastructure.”

Iran’s parliament speaker warned on Thursday that attacks on the islands on Iran’s southern maritime frontier would provoke a new level of retaliation, underscoring how central they are to the country’s economy and security.

Mohammad Bagher Qalibaf said in a social media post that Iran “will abandon all restraint” if the islands come under attack and that Trump will be responsible for “the blood of American soldiers.”

Explosion rocks area of demonstration

The explosion in Tehran rocked the Ferdowsi Square area midday, where thousands had gathered for an annual Quds Day rally, chanting “death to Israel” and “death to America.”

Israel had issued a warning on a Farsi-language X account for people to clear the area shortly before the blast. But few Iranians would have seen it, as authorities have almost completely shut down the internet. Footage showed people chanting “God is greatest,” as smoke rose in the area.

The Israeli military later posted a second message in Farsi, noting the head of Iran’s judiciary was at the rally and criticizing Iran for blocking many from seeing their warning.