US jets struck jihadist positions in northern Iraq today, a potential turning point in a two-month crisis Washington said was threatening to result in genocide and to expose US assets.
President Barack Obama's order for the first air strikes on Iraq since he put an end to US occupation in 2011 came after Islamic State (IS) militants made massive gains on the ground, seizing a dam and forcing a mass exodus of religious minorities.
Pentagon spokesman Rear Admiral John Kirby said on Twitter that US forces bombed the jihadists after artillery fire against Kurdish regional government forces defending their capital Arbil.
Two US jets hit a mobile artillery piece, he said. A Kurdish official said the strikes targeted the towns of Gwer and Makhmur, southeast of the autonomous Kurdish region.
The US operation began with air drops of food and water for thousands of people hiding from the Sunni extremist militants in a barren northern mountain range.
Many people who have been cowering in the Sinjar mountains for five days in searing heat and with no supplies are Yazidis, a minority that follows a 4,000-year-old faith.
Obama accused the IS, which calls Yazidis "devil-worshippers", of attempting "the systematic destruction of the entire people, which would constitute genocide".
The UN said it was "urgently preparing a humanitarian corridor."
Panic had begun to grip Arbil after IS thrust into the Nineveh plains separating the city from the main jihadist of Mosul and Obama's decision was welcomed there.
"We were very nervous these past few days. Daash (Islamic State) is powerful and well-equipped," said Karwan Ahmed, 27, a taxi driver. "This is good news."
The Kurdish peshmerga, short of ammunition and stretched thin along a huge front, have been forced to retreat in the face of brazen assaults by the jihadists.
Their withdrawal from the Christian heartland on Wednesday and Thursday sparked a mass exodus -- 100,000 people according to Iraq's Chaldean patriarch -- and spurred Western powers into action.
Obama's announcement came after an emergency UN Security Council meeting called by France, which also offered to support the emergency effort.
The capture of Mosul dam was another setback for the peshmerga who had been defending it and gave jihadists a power of life and death over a huge swathe of land.
A Kurdish and a local official said jihadists took it over on Thursday and warned that any "unscientific manipulation" could have disastrous consequences.
