Police were searching for a suspect in the deaths of two males and two females, and Sgt. David Sicilian of the Columbus homicide squad said they fear for the injured teen's safety.
"We obviously have a homicidal suspect out here who's not afraid to kill somebody. We need to quickly find out who that is or the persons responsible for this," Sicilian told reporters.
Police did not identify a suspect or motive in the slayings. They also said the ages and identities of the victims would not be released until relatives have been notified.
"It's a pretty ugly scene inside," Sicilian told The Columbus Dispatch.
A police dispatcher said earlier Saturday that the person found outside the home was a 16-year-old girl who wasn't believed to be seriously injured. Sicilian said he could not confirm the female's age or provide any additional details about her. She was treated at a hospital and released, police said.