Philadelphia police on Wednesday charged a 15-year-old girl with murder after she allegedly placed her newborn son in the trash in a North Philadelphia street.

The girl, Jani Morris, of West Lehigh Avenue, was arrested after the infant’s body was discovered Monday night, police said. She was charged with murder, endangering welfare, and related offenses.

Police originally said they had been contacted Monday night by a woman who told them she found a baby that had been placed in a dumpster by her daughter’s friend in the Swampoodle section of the city. Both the woman and the baby were taken to Temple University Hospital, where the infant was pronounced dead at 10:37 p.m., according to police.

A resident of the neighborhood, Diane Byrd, said in an interview Wednesday that she had been walking outside her rowhouse en route to church for midnight Mass on Monday when she ran into a woman frantically looking for help.

“She stopped in the street and was saying could someone help her find this baby, her daughter put it in the trash,” Byrd recalled, standing on her doorstep in the 2700 block of North Judson Street.

Byrd said the woman was checking trash bags along the sidewalk — there was no dumpster, she said — and ripped open a garbage bag and found her newborn grandson. Byrd said she ran over when the woman screamed, and saw the baby. The infant, she said, had been wrapped in plastic shopping bags before being placed in the larger bag.

“I’ve seen stuff like that on TV, but never a fetus in the trash," Byrd said. "I’ve never seen a baby in the trash like that. It was dead. It wasn’t moving or anything.”

When Byrd saw the dead child, she said, “Jesus, Jesus, Jesus,” she recalled.

Byrd said she didn’t know the woman or her daughter.

“We don’t know when she did it," Byrd added. “We don’t know how she did it.”

Byrd said she and four or five neighbors stood with the teen’s mother for a minute. “She was screaming,” Byrd said. “And then she put the baby in the backseat of her car.”

They tried calling police, Byrd said, but couldn’t get through. The teen’s mother told them that she had to go find the nearest police station and drove off. And then Byrd went to church.

“It’s just sad," said Byrd, who said she has lived on the block most of her life. The mother, she said, is "just a baby herself. But she still should have had enough common sense to not do that. There are plenty of people who have kids young. I had mine young.”

The teen’s mother has been cooperating in the investigation, according to Capt. Sekou Kinebrew, spokesperson for the department.

“It’s a tragic set of circumstances all around,” he said.