Despite spending time in the morning chill, with temperatures in the 30s, the baby boy, believed to be 1 day old, was reported in good condition at Children's Hospital of Philadelphia.

Police were looking for the mother, who could face abandonment charges she would not have faced if she had taken the child to a hospital.

Police Sgt. Charlie Marsden said a man who lives on the first block of South 58th Street saw the bag when he left to do some chores and buy a lottery ticket about 9 a.m.

When he returned about 11 a.m., he heard crying but could not determine its source, Marsden said. The man summoned his roommate and together they found the baby.

Marsden said the trash bag could have killed the child or saved his life.

"If the bag had gotten in his mouth, the baby would have died," he said. "But it also could have trapped heat and kept him warm."

Authorities said there was no need for the mother to abandon the child, risking his health and safety and making her liable for criminal charges.

Under state's safe haven law, any mother can leave a child at a hospital with no questions asked as long the child is less than 28 days old and unharmed.

Anyone with information about the abandoned infant is asked to call police at 215-686-8477 (215-686-TIPS).