The US and Israel traded air strikes with Iran across ​the Middle East on Wednesday as the besieged Tehran government warned its state security forces were ready with “fingers on the trigger” to confront any anti-government protests.

Following an exchange of ‌some of the heaviest bombardments in the region yet on Tuesday, the combatants renewed their attacks on opposing targets in Israel, Lebanon and the Gulf as the war stretched into its 12th day.

The conflict has effectively blocked vital shipping lanes through the Strait of Hormuz, halting the flow of one-fifth of the world’s fossil energy supplies from the petroleum-rich Gulf.

After a major surge in crude oil prices on Monday, global energy prices have tumbled and stock markets rebounded as investors bet that US President Donald ​Trump would seek to end the war soon.

Adding to market optimism, the International Energy Agency has proposed the largest release of oil reserves in its history to further stabilize crude prices, the Wall ​Street Journal reported on Tuesday, citing officials familiar with the matter. Reuters could not immediately verify the report.

Nevertheless, Iran’s Islamic Revolutionary Guard Corps vowed to block ⁠oil shipments from the Gulf unless US and Israeli attacks ceased. And air strikes between the two sides showed no immediate sign of abatement.

A cargo vessel was hit by an unknown projectile in the Strait of Hormuz, ​resulting in a fire onboard and prompting the crew to evacuate and request assistance, according to the United Kingdom Maritime Trade Operations on Wednesday.

The maritime body also said it had received a report of a separate ​incident off the UAE coast, with the master of a container vessel reporting it sustained damage from a suspected but unknown projectile.

The White House on Tuesday reiterated Trump’s threat to hit Iran hard over moves by Tehran to stop the flow of energy supplies through the Strait of Hormuz. The US Central Command said 16 Iranian mine-laying vessels had been “eliminated” near the strait on Tuesday.

Iran calls for Help in Targeting US, Israel

Millions of Israelis were repeatedly driven into bomb shelters overnight as ​the military warned Iran had launched missiles toward Israel, a sign that Tehran retains the capacity to strike Israel after nearly two weeks of hostilities.

The sound of explosions from air defences intercepting the rockets punctuated the ​pre-dawn darkness as air raid sirens blared and Israelis scrambled to safe rooms and shelters. There was no immediate word of whether any of the missiles reached the ground.

Iran’s armed forces spokesman Abolfazl Shekarchi on Wednesday urged regional countries ‌and fellow Muslims ⁠to indicate “US-Zionist (Israeli) hiding places” to maximise the precision and impact of Iranian strikes, while minimizing harm to civilians, who he said are “used as human shields”, according to Defapress, a news outlet affiliated with the military.

Shekarchi also said that Iran will respond to recent US-Israeli strikes in residential areas.

The latest attacks from Iran roughly coincided with a new Israeli barrage on Beirut aimed at rooting out the Iran-backed group Hezbollah, which has fired into Israel from Lebanon in solidarity with the Tehran government.

Large-scale rallies have been held in Iran in support of its newly named supreme leader, Mojtaba Khamenei, a hardliner chosen to succeed his father, who was killed on the ​war’s first day. A funeral procession for high-level Iranian ​military commanders killed early in the war will ⁠be held in Tehran on Wednesday from 1:30 p.m. (1000 GMT).

Tehran Warns Against Protests

Many Iranians want change and some openly celebrated the death of the elder Khamenei, weeks after his security forces killed thousands of people to put down anti-government protests.

But there has been little sign of protest during the war, and Iran moved to ​clamp down further on internal dissent days after Trump exhorted Iranian citizens to seize an opportunity afforded by US and Israeli attacks to rise up ​and overthrow their government.

Fearing a revival ⁠of anti-government demonstrations, Iran’s police chief Ahmadreza Radan warned that “anyone taking into streets at the enemy’s request will be confronted as an enemy not protestor.”

“All our security forces have their fingers on the trigger,” Radan told state television.

Iran also arrested dozens of people, including a foreign national, accused of spying for the country’s “enemies,” the Intelligence Ministry said on Tuesday.

More than 1,300 Iranian civilians have been killed since the US and Israeli air strikes began on February ⁠28, according to ​Iran’s U.N. ambassador, Amir Saeid Iravani. He said nearly 8,000 homes have been destroyed, along with 1,600 “commercial and service centres” and ​dozens of medical, educational and energy-supply facilities.

Scores have also been killed in Israeli attacks on Lebanon, while Iranian strikes on Israel have killed at least 11 people.

In addition to seven US soldiers killed in the conflict, the Pentagon on Tuesday estimated about 140 American troops ​have been wounded.