This Is What the Air Strike in Iraq Looked Like

-- The Defense Department has released video of an air strike that took place Friday in Iraq.

The video shows two F/A-18 fighter jets dropping laser-guided bombs on mobile artillery near Erbil. It begins with an overhead view over a target. Then a bomb drops before a flash of what appears to be a large cloud of smoke. Another shot, most likely from land, shows rising smoke from afar.

The United States military carried out three rounds of air strikes on Friday against ISIS militants in Iraq in its renewed effort to bolster the Iraqi and Kurdish forces against Islamic militants. The strikes targeted ISIS fighters, a stationary convoy, mortars and artillery, according to statements on Friday from Pentagon's press secretary, Rear Adm. John Kirby.

Kirby said two fighter jets dropped 500-pound, laser-guided bombs on a mobile artillery piece. Kirby said the artillery was being "used against Kurdish forces defending Erbil, near U.S. personnel." The fighter jets that dropped the bombs came from the USS Bush aircraft carrier in the Persian Gulf, according to the U.S. Navy.

Later on Friday, an armed drone struck an ISIS mortar position shortly after 10 a.m. local time. A follow-up attack was launched on the ISIS fighters when they returned to the location "and successfully eliminated" the target, Kirby said.

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A little more than one hour later, four F/A-18 aircraft hit a stationary convoy of seven vehicles and a mortar position near Erbil, the capital of the Kurdish autonomous region. According to Kirby, the fighter jets conducted two passes, dropping a total of eight bombs on the target, wiping out the mortar and convoy.

The attacks come one day after President Obama authorized air strikes in Iraq if necessary, adding that there will be no U.S. troops on the ground.

It has been nearly three years since U.S. forces left Iraq and three years since Obama announced the war there was over. The last convoy of U.S. soldiers left Iraq in December 2011.

Administration officials believe the Iraqis are best suited to deal with the threat of ISIS, the Islamic State of Iraq and Syria, over the long term.

"We're laying down a marker here that even though [ISIS] is not penetrating Erbil, just their presence on the periphery, and the potential threat they pose, could lead us to take action if the targets present themselves," an official told ABC News.

U.S. forces are conducting a difficult and dangerous humanitarian mission, with three U.S. Air Force cargo jets escorted by two F-18 fighter jets dropping critical supplies. In a race to stop a catastrophe, thousands of families who fled to the top of a mountain in Sinjar now face a worrisome predicament, battling blistering heat, pleading that there is no water or bread. Nearly 20 children have already died. They are trapped 3,000 feet up with no escape.

Down below, ISIS terrorists have taken over their homes, warning of a slaughter if they return.

The U.S. aircraft dropped 5,300 gallons of water and 8,000 ready-to-eat meals.

Senior administration officials said air drops and humanitarian aid will continue "as we see need," and the administration expects that need to continue.

The White House believes any action would be consistent with international law, because U.S. input was requested by the Iraqi government.

Additionally, the administration believes that the president has the legal authority under the Constitution to act to protect U.S. citizens.

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