Two children, 7 and 3 years old, sustained serious injuries after falling out of the window of an apartment in Otay Mesa Thursday night.
It's unclear how far the children fell, but both were rushed to Rady Children's Hospital, San Diego Fire-Rescue Battalion Chief Matt Nilsen said.
A person at the home who identified himself as a family member said the children were playing when they bumped into a screen and fell out the window.
The apartment complex is on Sandcliff Lane south of Ocean View Hills Parkway.
A neighbor told NBC 7 the design of some windows in the complex makes it easy for kids to sit on the sill.
"It's definitely easy ... if you sit up there and the window is open, it's pretty easy to fall down," the neighbor said.
"I hope they're OK. That's all I can say as a parent," another neighbor said.
SDPD is investigating. This story will be updated as more information is released.