KHAZER CAMP, Iraq — President Obama justified the US military’s return to fighting in Iraq on Saturday by saying America must act now to prevent genocide, protect its diplomats, and provide humanitarian aid to refugees trapped by Islamic State militants on a mountain ridge near the Syrian border.
‘‘This is going to be a long-term project’’ that won’t end and can’t succeed unless Iraqis form an inclusive government in Baghdad capable of keeping the country from breaking apart, Obama said at the White House.
US planes and drones launched more airstrikes on Islamic State forces Sunday. US Central Command said the strikes destroyed armed vehicles, including one that was firing on Kurdish forces in the approaches to the city of Irbil, and a mortar position. The military said the airstrikes took place from about 2:15 a.m. Eastern Daylight Time Sunday to about 5:45 a.m.
It was the fourth round of airstrikes against Islamic State forces by the U.S. military since they were authorized by President Barack Obama
The military support also has been helping clear the way for aid flights to drop food and water to thousands of starving refugees in the Sinjar area.
But the help comes too late for many of the religious minorities targeted for elimination by the Islamic State group, which swept past US-trained and equipped Iraqi government forces in recent weeks and now controls much of Iraq.
A delayed response by the Shi’ite-led government in Baghdad left Kurdish forces struggling to contain the Sunni extremists’ advances. With nowhere to go but uphill, Kurdish-speaking Yazidi refugees sought shelter in the mile-high Sinjar mountains, where their ancient religion holds that Noah’s ark came to rest.
US, Iraqi, and British cargo planes dropped tons of food, water, tents, and other equipment to the refugees Friday and Saturday. Iraq’s defense ministry released a video showing people in the Sinjar mountains rushing to collect food and water as the Iraqi government’s fleet of C130 cargo planes dropped 20 tons of aid at a time.
But at least 56 children have died of dehydration in the mountains, UNICEF’s spokesman in Iraq, Karim Elkorany, told The Associated Press on Saturday.
British officials estimated Saturday between 50,000 and 150,000 people could be trapped on the mountain.
And Juan Mohammed, a local government spokesman in the Syrian city of Qamishli, told the AP that more than 20,000 starving Yazidis are fleeing across the border, braving gunfire through a tenuous ‘‘safe passage’’ that Kurdish peshmerga forces are trying to protect.
With shocked, sunburnt faces, men, women, and children in dirt-caked clothes limped to a camp for displaced Iraqis on Saturday, finding safety after harsh days of hiding on a blazing mountaintop, fleeing the Islamic State extremists.
Children who died of thirst were left behind and some exhausted mothers abandoned their babies as thousands of Yazidis trekked across a rocky mountain chain in temperatures of more than 100 degrees, crossing into neighboring Syria, and then looping back into Iraq to reach safety at the Bajid Kandala camp.
Other Yazidis have settled in refugee camps in Syria: So awful is their situation, they have sought safety in a country aflame in a civil war.
The US military officially withdrew its combat forces in late 2011 after more than eight years of war. It returned to battle Friday when two F/A-18 jets dropped 500-pound bombs on Islamic State fighters advancing on the Kurdish capital of Irbil as violence sent the number of displaced Iraqis soaring.
General Ahmed, the peshmerga spokesman at the Khazer checkpoint on the frontline outside Irbil, said it was a ‘‘good hit,’’ but the impact wasn’t yet clear. The Kurdish general spoke on condition his last name not be used.
Obama was adamant Saturday that US troops can’t bring peace to Iraq.
‘‘We can conduct airstrikes, but ultimately there’s not going to be an American military solution to this problem. There’s going to have to be an Iraqi solution that America and other countries and allies support,’’ he said.
The Pentagon said the militants were using the artillery to shell Kurdish forces defending Irbil, the capital of Iraq’s autonomous Kurdish region, home to a US consulate and about three dozen US military trainers.
Iraq’s embattled prime minister, Nouri al-Maliki, waited until Monday to call in aerial reinforcements for Kurdish fighters trying to contain the Islamic State’s advance. It was his government’s first show of cooperation with the semi-autonomous Kurdish regional government since Iraq’s second largest city, Mosul, fell to the extremists in June.
And so Kurdish officials were particularly pleased by the return of US air support as well as the military trainers coordinating tactical responses with Kurdish peshmerga forces in Irbil.
‘‘Air strikes are intended to degrade the terrorists’ capabilities and achieve strategic gains — and have been very effective,” said Iraqi Foreign Minister Hoshyar Zebari, a Kurd.
Many of America’s allies have backed the US intervention since the Yazidis’ plight gained attention. British forces are coordinating aid drops with the US and, more broadly, trying to figure out how to help the refugees escape from ‘‘a completely unacceptable situation,’’ British Defense Secretary Philip Hammond said.
The Yazidis follow an ancient religion with roots in Zoroastrianism, which the Islamic State group considers heretical and has vowed to destroy. The extremist group also considers Shi’ite Muslims to be apostates and has demanded that Christians convert to Islam, pay a special tax, or be killed.