HATAY, Turkey — For four days straight, Russian air strikes and Syrian barrel bombs have pummeled Idlib, prompting a dire warning from the United Nations. The attacks have displaced 30,000 people with nowhere to go.

"There needs to be ways of dealing with this problem that don't turn the next few months in Idlib into the worst humanitarian catastrophe, with the biggest loss of life, of the 21st century," said Mark Lowcock, the under-secretary-general for humanitarian affairs and emergency relief coordinator.

Nearly 3 million civilians are on the ground, including 1 million children. After more than seven years of civil war, they face a familiar choice — get away as fast as you can, or stay put and risk death.

But half the people here have already fled from other parts of Syria and they have nowhere left to go. So they stock up on resources and fit children with homemade gas masks.

Meanwhile, emergency workers resume the grim routine of collecting the dead, saving the injured and putting out fires. But they are not immune, since they're at risk of explosions.

While the bombs fall, the diplomats meet. In Geneva, the UN and Russia are discussing a new Syrian constitution, far removed from Idlib, where constitutional rights are powerless to stop a bloodbath.