D.C. Police Chief Cathy L. Lanier asked for the public’s help Tuesday in identifying the parents of an infant girl who died after being abandoned Sunday night on the doorstep of a Northeast Washington home.

“There is somebody out there who knows or who has some suspicions of who may be the parents of this baby girl, and we need them to come forward,” Lanier said at a news conference.

A man walking in the 3000 block of Channing Street NE about 11 p.m. Sunday saw a bundle on a doorstep and realized that it was an infant loosely wrapped in a towel. The child was stiff and bleeding from the nose and mouth, said Emmanuel Dugger, 35, who made the discovery. Hours later, authorities pronounced the baby dead.

Lanier did not comment on the baby’s condition or whether she had any distinguishing marks. She described the child as an African American who was 1 month old or younger. The autopsy might better pinpoint her age as well as the cause of death, Lanier said.

“It’s really important to us that we try and find the person who delivered this child,” Lanier said. “We want to really try and get some answers for the baby girl.”

Mayor Vincent C. Gray (D) took to Twitter to reinforce the chief’s plea and express the shock and sadness that reverberated throughout the city Tuesday — particularly because the District has a safe haven law, which allows a parent to leave an unharmed baby at a hospital, police or fire station — no questions asked.

“The death of an abandoned infant discovered Sun night in NE is a horrific tragedy. Help @DCPoliceDept identify her,” Gray tweeted.

Homicide detectives are assigned to the case, which is common for any death investigation, Lanier said, but “at this point, we don’t have any new developments.” Without knowing how the child died, “we don’t even know if a crime has been committed,” she said.

Ian Milne, 31, lives in the Wood­ridge house where the baby was discovered. Milne, a teacher and father of two, said that he frequently walks around the neighborhood with his children and that there are toys strewed in front of his home.

“We’re racking our brains trying to figure out why the baby was left here,” Milne said. He said he learned about what happened when Dugger knocked on his door Sunday; then he saw a firetruck. “I was in disbelief,” Milne said.

The last time an infant was found abandoned in the District was in the summer of 2007, said Mindy Good, a spokeswoman for D.C. Child and Family Services. The boy was left on a doorstep and discovered by a woman on her way to work. That child was in good health and was taken into custody by the agency, Good said.

Lanier said anyone with information on the abandoned girl or her parents can send an anonymous text message to 50411 or call 202-727-9099.