Iranian Supreme Leader Ayatollah Ali Khamenei has gone into hiding out of fear U.S. forces will kill him in airstrikes, reports the Jerusalem Post.

The report comes a day after President Donald Trump said an "armada" of U.S. ships is headed to the Middle East amid mass protests in Iran.

"We have a lot of ships going that direction just in case," Trump said when he was asked by reporters on Air Force One where things stand with Iran.

He said it was a "good sign" Iran had decided not to hang protesters, adding that "we have an armada heading that direction and maybe we won't have to use it."

According to the Post, Masoud Khamenei, the ayatollah's third son, has assumed oversight of the supreme leader's daily operations and now serves as the main conduit for communication with the regime's executive branches.

The commander of Iran's paramilitary Revolutionary Guard Corps, which was key in putting down recent nationwide protests in a crackdown that left thousands dead, on Saturday warned that his force is "more ready than ever, finger on the trigger," as U.S. warships headed toward the Middle East.

Nournews, a news outlet close to Iran's Supreme National Security Council, reported on its Telegram channel that the commander, Gen. Mohammad Pakpour, warned the United States and Israel "to avoid any miscalculation."

"The Islamic Revolutionary Guard and dear Iran stand more ready than ever, finger on the trigger, to execute the orders and directives of the Commander-in-Chief," Nournews quoted Pakpour as saying.

Tension remains high between Iran and the U.S. in the wake of a bloody crackdown on protests that began on Dec. 28, triggered by the collapse of Iran's currency, the rial, and swept the country for about two weeks.

Meanwhile, the number of people reported by activists as having been arrested jumped to more than 40,000, as fears grow some could face the death penalty.

The Associated Press contributed to this report.

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