HWAIDA SAAD

After nearly five years of civil war in Syria, the United Nations estimates that 400,000 people are trapped behind battle lines by the government, the Islamic State or rival insurgents.

In the hills near the Lebanese border, an hour’s drive from downtown Damascus, much of a Syrian town is starving, according to residents and international humanitarian workers.

The bombings, near a Palestinian refugee camp that has absorbed many Syrians, killed at least 43 people, according to the Lebanese Health Ministry.