Authorities are trying to determine how a 4-year-old boy was mauled Saturday night by two dogs that had been crated at his uncle's house in Riverview.

According to the Hillsborough County Sheriff's Office, two deputies were conducting a traffic stop near the home on the 12500 block of Rhodine Road when they heard a child's screams.

They ran to the scene and found young Logan Shepard in the front yard with the two dogs, described by deputies as pit bulls, standing over him. The child was pronounced dead at the scene around 10:30 p.m.

Investigators say Logan and his mother, Stephanie Groulx, had walked from their home on nearby Tocci Lane to their aunt and uncle's residence. The uncle, Bill Fredericks Sr, had crated the two dogs before their arrival.

Logan was given some ice cream once inside the house and was left sitting in the family room while the adults and Logan's 15-year-old cousin went into the master bedroom to talk.

The adults then heard screams and came out of the bedroom to discover Logan was not in the house. The deputies arrived moments later.

Animal Services responded to the home and took possession of the dogs. It was the first call to the home for a problem with the dogs, authorities said.

No charges have been filed, but authorities are still investigating. Deputies said Groulx and the aunt, Delores Fredericks, are sisters.