The 20-year-old recent high school graduate had finished his day at his food distribution plant job when he stepped onto the wrong bus. He got off in the neighbourhood of Seminole Heights and began walking to another bus stop to make his way home.
As the hours ticked by, Naiboa's father Casimir and his stepmother Maria Rodriguez started to become worried. Casimir went so far as to report their missing son to authorities.
The police presence was high in the neighbourhood at the time, due to the two other shocking murders that had gripped the city in the past 11 days. When officers heard gunshots about 8pm, they rushed towards North 15th St.
But they were too late.
When a TV report beamed out a news flash at 10pm about a body being found, "I felt a chill go down my spine", Casimar Naiboa told the Tampa Bay Times. A police officer turned up a few hours later with some "bad news".
"He didn't need to say anything else," Casimar Naiboa said.
Naiboa's murder on Thursday night was the third in a shocking spree that has spread the fear throughout this historic neighbourhood and this Florida city as a whole that a serial killer is on the loose.
The slayings began on October 9 when Benjamin Mitchell, 22, was shot dead near a bus stop also on North 15th St, about 90m from where Mr Naiboa was found.
Monica Hoff, 32, was shot dead on October 11 on East New Orleans Ave 10 blocks away, but her body was not discovered until two days later, dumped in a vacant lot.
Police have been hesitant to use the words "serial killer", but they are working on the assumption that the murders are related.
The theory is that the victims were chosen at random, given they have few meaningful links. Mitchell and Naiboa were acquaintances, having attended the same high school, but police believe it is the circumstances of each murder that are more significant.
A disturbing pattern has emerged. Each victim was walking on the streets alone at night, soon after getting off a bus. They were killed a few blocks away from each other, all within a two-week time frame. All were killed by a gunshot.
None were robbed and race does not appear to be a motivating factor, given that the first victim was African American, the second was Caucasian and the third was Hispanic. Tampa police chief Brian Dugan has admitted investigators have no suspects, no leads and no motive. The FBI has been called in to help crack the case.
The only clue police have revealed to the community is creepy security camera footage of a hooded man walking through Seminole Heights on the night of the first murder.
Interim Police Chief Brian Dugan speaks at a press conference regarding the recent three murders in the Seminole Heights neighborhood. Photo / AP
Dugan prompted gasps at a packed community meeting on Monday night when he said, "everybody, at this point, is a suspect".
"There's a very good likelihood that some in this room knows who's doing it," he said, according to CBS News.
"This pains me to tell you that if you're out there walking alone that you're either a suspect or a potential victim."
With Halloween a week away, police have flooded the streets with officers to keep an eye out and make the community feel safe.
Officers have escorted children to school, kept a close eye on bus stops and gone so far as to hand out light bulbs so citizens keep their veranda lights on at night.
The city has cleaned rubbish out of alleyways and trimmed back shrubbery to avoid giving the killer places to hide, and the police chief has warned citizens against walking the streets alone at night.
"The fact is you can't drive a block without seeing some sort of police presence, officers on foot. We are a 24/7 presence," Tampa Police Department spokesman Stephen Hegarty told news.com.au.
"People are feeling on edge, some businesses are not being visited as frequently as they would like.
"The chief has told people to go out an live your life and walk your dog, just do it with a friend or two - because these murders happened to people who were alone.
"We're not telling people to just hunker down, just don't take a walk alone at night."
Despite the legitimate concerns in the community, Hegarty said there was still a "sense that we're not going to be afraid".
"We hope to get a breakthrough because this is wearing on people in the community," he said.
A makeshift memorial for shooting victim Anthony Naiboa sits on a sidewalk. Photo / AP
While some have taken to the streets, walking in 50-strong groups as a sign of solidarity, many residents have taken to barricading themselves inside their homes.
