Dismembered baby
The baby's arm and head were found in the garden of a Westmont home.

A nine-year-old US girl uncovered the dismembered remains of a baby while playing in her backyard.

Britany Placencia was playing with her dog at home at 10am on 26 April, in the Los Angeles suburb of Westmont when she made the grisly discovery.

"The dog was sniffing the ball, so I was going to get the ball and I got it," she told CBS Los Angeles. "I saw the leg, so I just ran to my mom and told her."

At first Britany's mother thought it might have been a chicken leg, but quickly realising it was the remains of a newborn child.

The baby's head was found next to the family's fence.

Los Angeles County Sheriff's Department homicide detectives said the remains were of a one to three-day-old child.

A statement from the sheriff's office said: "The infant appears to have been dismembered. Significant portions of the body are still missing."

Police have urged local residents to search their gardens and bins, saying the infant's killer may have discarded the rest of the remains.

Detectives said they would also like to speak with "any females who were recently pregnant, are no longer pregnant, and the baby is absent".