SAN FRANCISCO (CBS SF) -- San Francisco police have boosted the reward for information to $250,000 in the 2016 homicide of Nicole Fitts and the search for her missing toddler Arianna Fitts.
The body of Nicole Fitts was found buried in the city's McLaren Park on April 8, 2016. She had been reported missing by her family members along with her two-and-a-half-year-old daughter Arianna. Police said investigators determined the child was in the care of her babysitter and her husband at the time of her disappearance and that Fitts was lured to meet the babysitter during the time of her disappearance.
"We know there's an explanation for what happened," said San Francisco police acting commander of investigations James Aherne. "This is a tragic situation for everyone involved and we know people associated with this matter want to be heard. We want to hear from you. We will listen to you. We continue to have an open mind and are considering all possibilities."
FBI assistant special agent in charge Scott Schelble said in the last few months investigators have developed many new leads, new people have come forward with information and additional evidence has been recovered.
"Additionally, there have been significant advances both in digital and biological forensic evidence that is allowing us to see much more than what we knew six years ago," said Schelble.
Schelble added that investigators can't reveal everything they know about the case and they hope more people will jostle their memory and come forward.
"We believe there are multiple people with direct knowledge of this case who have not fully cooperated with law enforcement," said Shelby. "We believe there's an even a larger circle of people with indirect knowledge of what happened. Perhaps you heard of something or thought of something that night. Perhaps you know more of Nicole's last movements or have heard some information about Arianna's whereabouts. We are asking you please to come forward to law enforcement."
Police on Friday released a new age-progression image of what Arianna might look like. Last year, the FBI released an age-progressed sketch hoping to generate leads as to where the little girl may be.
Police have previously offered a $100,000 reward for information leading to the arrest and conviction of those responsible for the crimes.
"It makes me sad, because I can't see her smile anymore and it makes me angry because that was stolen," said Nicole's sister Tess Fitts. Tess shared memories of the young mother at a memorial on Friday. "It was rare to not see a smile on Nikki's face, even when times were hard for her, she still put on a good face," Tess said.
"Nikki has taught me compassion in the best way, and before I knew it, I was following," said Nicole's friend Claire Bonnar.
Nicole's Best Buy co-workers also showed up at the memorial to honor her memory. She was an employee and still dressed for work the night she went missing.
KPIX correspondent Betty Yu contributed to this report
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