Transcript for Suspected serial killer may have taken a 4th life in Tampa neighborhood
We are following the manhunt at this hour. FBI agents going door to door. Authorities say a serial killer in Tampa has struck again. ABC's Victor Oquendo from Tampa tonight. Reporter: In Tampa today, a front doorbell camera capturing the FBI going door to door. FBI. Reporter: Residents urged to stay inside while teams hunt for the killer they say could be hiding out in their own neighborhood. I've got a male down in the middle of the street on Nebraska. Reporter: Police arriving just before 5:00 A.M., right after the gunman claed his suspected fourth victim. The shooter ran east. Reporter: Witnesses telling officers they missed the suspect by just five seconds. Describing him as thin black man, about six feet tall. This has got to stop. We need to catch this killer before we have to notify one more family that one of their loved ones is dead. Reporter: The latest victim, 60-year-old Ronald Felton, who was on his way to feed the homeless at a local church, when he was shot from behind. His family today saying Ron enjoyed helping others. I love him, but he's still going to be in me. He's going to be in my heart. Reporter: For weeks, police asking the public to help them identify this person of interest, spotted on multiple cameras, near the scene of the first of three murders in October. Those victims killed at night, blocks apart, shot at random. Felton now killed in that same neighborhood. We talked to one neighbor who heard the gun shots this morning and asked we not show her face. This is a stun gun. It looks like a cell phone. Now thinking about buying a real gun. I think it's the best way, but it's scary. Quite scary, so -- Victor 0 KWEN toe live with us tonight. And we understand that neighborhood was on lockdown for much of the day. That lockdown now lifted, but not without reminding everyone to be extremely vigilant? Reporter: David, late today, police clearing this neighborhood, also reopening the street right behind me, which is where the shooting took place. Residents are allowed to leave their homes, but police want to make sure they look through any home surveillance video and make sure that any weapons or guns that they might own are secure and accounted for.
This transcript has been automatically generated and may not be 100% accurate.