Austin, Texas ? Police on Wednesday were pleading for witnesses to help them track down members of an angry mob that beat a man to death after the car he was riding in apparently struck and injured a child.

Investigators were struggling to piece together what happened Tuesday when David Rivas Morales died defending the driver from members of a crowd leaving a Juneteenth celebration. There could have been anywhere from two to 20 attackers, Austin Police Commander Harold Piatt said.

The car in which Morales, 40, was a passenger had entered an apartment complex’s parking lot when it struck a 3- or 4-year-old child, Piatt said. The child was taken to a hospital with nonlife-threatening injuries.

The driver got out of the car to check on the child and was confronted by several people, Piatt said. When they attacked the driver, Morales got out of the car to protect the driver and was attacked as well. Police said no guns or knives were used.

The driver got away and is cooperating with investigators, who are not releasing his name.

Margaret Morales said a young boy came to her door to tell her that her brother was lying on the ground outside. She found David Morales, sprawled on the pavement 100 feet from her townhouse, battered and choking on blood.

Police arrived one minute after receiving a 911 call, by which time the beating had stopped, department spokeswoman Toni Chovanetz said. But the Morales family complained that medical help was slow in coming.

David Morales arrived at the hospital about 35 minutes after the 911 call was received, said Warren Hassinger, Austin-Travis County Emergency Services spokesman. Emergency officials said police ordered them to wait until the area was secure.

A preliminary autopsy listed blunt force trauma as the cause of death.

An estimated 2,000 to 3,000 people were in the area for a city-sponsored festival for Juneteenth, which commemorates Texas slaves getting the word that they had been freed.

Several hundred people had filled the parking lot and street as the daylong festival at a nearby park ended and spilled over into the surrounding neighborhoods, said Katherine White, a Morales family friend who lives in a townhouse next door to where the beating took place.

Police said the injured child was a girl, but White said it was a boy with long hair he wears in ponytails.