Undeterred and infuriated by Western accusations of war crimes and barbarity in the aerial assault on Aleppo, the Syrian government and its ally Russia intensively bombed the city in northern Syria on Monday for the fourth consecutive day. Residents and rescuers there described the bombardment as among the worst yet in the five-year war.

Both the Kremlin and the Syrian government appeared to harden their position that the United States and its partners had caused the disintegration of a fleeting cease-fire last week. The Russians went as far as suggesting that the Western portrayal of them as war criminals in the Syria conflict risked a further alienation in relations.

Insurgent-held neighborhoods in eastern Aleppo were hit with dozens of air attacks in the predawn hours, killing and wounding many people, according to doctors, nurses and activists in the city. By some estimates the deaths totaled 100 or more for the fourth day.

A number of monitor groups disseminated graphic photos and video clips portraying the medical mayhem wrought by the bombings.