(CNN) The mayor of Tampa has a message for police officers hunting down a mystery killer: "Bring me his head on a platter."

"I'm mad because those three families had a huge hole ripped in their hearts," Mayor Bob Buckhorn told CNN's Mike Galanos . "That scumbag who did that, we're coming for you. I told them (officers), 'bring me his head on a platter. '"

The video, taken at different angles, shows the same person seen in the historic Seminole Heights neighborhood in an earlier video released by police.

"I've come up with four reasons why this person is running," interim Tampa Police Chief Brian Dugan told reporters. "One, they may be late for dinner. Two, they're out exercising. Three, they heard gunshots and, number four, they just murdered Benjamin Mitchell."

The victims

Benjamin Mitchell, 22, was shot and killed in front of his home on October 9.

The second victim, Monica Hoffa, 32, was killed two days later. Her body was found by a city employee in a vacant parking lot half a mile from where Mitchell died.

Then a week ago, Anthony Naiboa, 20, who had just graduated from high school, became the third victim when he accidentally got on the wrong bus after leaving work and ended up in the southeast Tampa neighborhood, police said.

Authorities believe Naiboa was making his way to another bus stop. He did not get more than 200 yards before he was shot and killed October 19.

The three victims were alone and found within about a half-mile of each other, Dugan said.

WATCH VID: https://t.co/XwauE5YCHG

We believe this person may have ties to the Seminole Heights area. Contact @crimestopperstb pic.twitter.com/QAmp8UTlMf — TampaPD (@TampaPD) October 26, 2017

No clues, no motive

From left, Benjamin Mitchell, Anthony Naiboa and Monica Hoffa were killed within 11 days in a Tampa, Florida, neighborhood.

Dugan said the person in the video is not considered a suspect in the string of shootings, but he may have answers.

"He may have seen something or heard something," the chief said of the person seen flipping what appears to be a cellphone in their right hand while walking.

Any clue, any little detail such as the phone flip, may lead to a break in the case, authorities said.

"That might be a habit of this person," Dugan said of the phone flip. "At this point, everything is a clue, everything is a speculation."

In the video, the person is seen walking in one direction, then running the opposite way seconds after Mitchell was shot.

"We believe this person has ties to this neighborhood and we want to speak to them," Dugan said.

Buckhorn said officials don't have many leads on the killer or the motive.

"I'm mad because I feel my community has been violated," Buckhorn said Thursday. " I'm mad because these good folks here ... many of whom I know, are being held hostage by this person."

Another surveillance video

Police are asking for clues on the person in this surveillance video.

Last week, police released a surveillance video of the same person walking in the area.

Buckhorn said they didn't have any description of a suspect or suspects, and have so far avoided calling the suspect a serial killer.

"We're not using the word 'serial killer' yet because we just don't have enough evidence," Buckhorn said. "We're not afraid of that word -- if we think that that's true, we'll be happy to say it. But we've got to connect the dots."

As the investigation develops, Dugan said there will be a large police presence in Seminole Heights. He urged residents to turn on their porch lights and keep an eye on the streets.

The city has cleared alleys, added streetlights and cut undergrowth to ensure visibility