DETROIT -- A man was in police custody Tuesday in connection with the death of a 9-year-old girl in Detroit who was mauled by three dogs despite efforts by neighbours and her own "heartbroken" father, who lamented that "she was gone when I reached her."

Emma Hernandez was riding her bike in an alley Monday afternoon when three dogs, described as pit bulls or pit bull mixes, got free from a yard and attacked her, police said. She died later at a hospital and the dog's owner has been taken into custody. No charges have been filed, though police sent a warrant to prosecutors.

"I tried my best. I tried CPR. I tried helping her. I did everything I could in my power," Emma's father, Armando Hernandez, told WWJ-AM on Tuesday. "She was gone when I reached her."

One of the dogs was shot and killed by a bystander while a medical crew tried to save the girl in an alley. The other dogs were captured. Neighbors threw bricks at the dogs to try to stop the attack, police said.

"They were not stopping," Edward Cruz, who hurled a brick after hearing screams, told The Detroit News. "I had to step in."

Hernandez said the dogs lived at a house behind his, and he had an argument last week with the neighbour about them. Hernandez says the dogs weren't properly restrained and the fence was too flimsy.

"I knew the dogs were there. I knew the neighbour," he said. "We had an argument about it just last week and he just didn't take care of his dogs properly. He could have prevented this."

The dogs will likely be euthanized, city officials said.

Hernandez said he keeps replaying the tragedy and feels "empty."

"I'm really heartbroken right now. I can't explain it," he said. "Just, every time I close my eyes, man, I see my baby girl."

Detroit police Chief James Craig on Tuesday afternoon called the case "tragic" and "distressing."

"The owner of these dogs should be held accountable," he said. "Certainly the owner has a responsibility when they have violent animals that those animals are to be secured at all times. If you can't secure the animal, you shouldn't have the animal. Period."

The incident follows the December 2015 death of Xavier Strickland, a 4-year-old Detroit boy who was attacked with his mother by four pit bulls. Police had to shoot them to free the boy's body.

The dogs' owner, Geneke Lyons, was convicted several months later of involuntary manslaughter. Lyons wasn't home at the time of the attack, but prosecutors said he should be held responsible because the dogs weren't under control. A judge earlier dismissed a second-degree murder charge.

Numerous pit-bull maulings have made headlines in Michigan and elsewhere. A 2014 American Veterinary Medical Association report says pit bulls are not disproportionately dangerous, though owners of pit bull-type dogs deal with a strong breed stigma. However, some advocates for breed-specific community ordinances say pit bulls are behind most fatal dog bites.

The Michigan Senate last year passed legislation that would have prohibited local governments from dictating breed-specific regulations on dogs. The measure made it through a House committee but never got a vote from the full chamber.

At least 20 states prohibit such legislation.