Hundreds of people have been killed since Tuesday in a government push to quash rebels in eastern Aleppo.
The move comes ahead of a "humanitarian pause" meant to allow civilians and rebels to leave the city.
Many children were among the dead.
The Syrian government, with Russian-backed forces, is trying to take back the city from rebels.
“The warplane flew over us and directly started dropping its missiles on this hospital," a doctor says.
“The planes are not leaving the sky, helicopters, barrel bombs, warplanes," one resident said.
Footage of a 5-year-old being taken to an ambulance recalls a graphic photo that surfaced last fall.