Police have arrested the mother of a newborn baby that was abandoned in a stroller on a Los Angeles street.

Police say 20-year-old Belen Ramirez of Long Beach was arrested early Saturday morning on suspicion of child endangerment. She remains jailed and it's unclear if she has an attorney.

The boy's umbilical cord was still attached when a passerby found him in stroller near a church Tuesday afternoon, not far from the University of Southern California.

Investigators say the boy was about a day old.

The child is in good condition and remains in official custody.

Los Angeles County's "Safe Surrender" law allows a parent or guardian to give up a newborn at a hospital, fire station or other approved site if the child shows no signs of abuse.