WASHINGTON — The US military flew two B-52 bombers to the Middle East on Thursday from their base in the United States — the fourth such deployment and show of force by the US Air Force aimed at sending a message to Iran in the past two months.

This latest mission was to "demonstrate the US military's continuing commitment to regional security and deterrence to aggression," the Air Force said in a statement and comes amid concerns Iran may still seek to retaliate for the assassination of Tehran's top military commander in a US drone strike just over a year ago.

The move suggests there will be no let-up in the US deterrence campaign as tensions remain high less than two weeks before President-elect Joe Biden takes office.

"The aircrews flew a 36-hour, non-stop mission from the 5th Bomb Wing's home at Minot Air Force Base, North Dakota, to the Arabian Gulf and back to send a clear deterrent message by displaying the ability to deploy overwhelming combat power on short notice," the statement said.

"We continue to see increasing levels of readiness across Iranian defensive systems, and continue to have indications of advanced planning for potential attacks in Iraq, though it is unclear if and when they may move forward with an attack," a defense official said of movements in the region.

There is a broad sense of concern that adversaries could take advantage of the domestic turmoil in the US but as of now, there is no indication of any elevated threat tied to the riots that took place at the Capitol in Washington on Wednesday.

Earlier this week, President Donald Trump directed acting Secretary of Defense Christopher Miller to reverse course and order a US aircraft carrier to return to the Middle East following a White House meeting Sunday, according to a senior defense official.

This decision overturned Miller's order last week to send the USS Nimitz out of the region and home, in part, to send a de-escalation signal to Iran amid rising tensions between Washington and Tehran.

Last week CNN reported there have been conflicting messages that reflect divisions within the Pentagon on the current threat level from Iran.

The B-52H "Stratofortress" is a long-range, heavy bomber that can perform a variety of missions. The bomber can fly at high subsonic speeds at altitudes reaching 50,000 feet. It has an unrefueled combat range in excess of 8,800 miles. The B-52H can carry precision-guided ordnance with worldwide precision navigation.

The move comes days after the one-year anniversary of the assassination of Iranian Gen. Qasem Soleimani in a US drone strike, a day that some US officials had worried Iran would mark with retaliation but that passed without violence.

The US has scaled up its military presence in the Middle East in a show of deterrence that included sending nuclear-capable B-52 bombers to the region, publicizing the transit of nuclear submarines near the Persian Gulf and, on Sunday, Trump's decision to extend the USS Nimitz's stay in the area.

Last week, Iranian Foreign Minister Javad Zarif charged that the US was creating a pretext for war. But Soleimani's successor marked his death by pledging that "those who took part in this assassination and crime will not be safe on earth. It's definite." — Courtesy CNN