Delray Beach police said they found a 2-year-old boy completely naked running in the street with a pit bull on a leash.
And back at the boy's home they found his dad, who "appeared not to be concerned," police said.
Police arrested Charles Thomas, 21, on Wednesday on a child neglect charge.
Officers were on patrol near Southwest Tenth Avenue and Southwest First Street just before 5 p.m. when they were flagged down by a woman.
In the street, they saw a 2-year-old with no clothes running down the street, holding a leash with a pit bull and heading toward Atlantic Avenue.