Police have released CCTV images of a man they want to question over the death of nine-year-old Lilia Valutyte.
Lilia was stabbed to death while playing with her sister outside a cafe in Boston, Lincolnshire, on Thursday.
Officers arrested two men in the aftermath of the killing, however they have now been released with no further action.
Lincolnshire Police has now released a picture of a man it wishes to speak to, although the force warned Brits to not approach him.
Chief Superintendent Martyn Parker said: “Our officers have been working round the clock on this investigation, and the public’s help may prove crucial.
“These are very clear images of a man we want to speak to, so I’d urge anyone with information to get in touch with us. If you see him, do not approach him but immediately call 999.
“This is a particularly tragic case and I’d like to reassure the public that we have a huge amount of resources dedicated to the investigation.
“We continue to provide support to the family of Lilia, as they grieve following this unimaginable loss.”
The man police want to speak to was dressed in a light t-shirt and dark trousers in the released CCTV images.
Lilia was killed while playing outside the cafe where her mum worked, The Sun reports.
The mother was reportedly watching her girls play through the window of the cafe.
She was the first on the scene after the stabbing, rushing to her daughter’s side, according to The Sun.
A local told the newspaper: “Her mum had a business inside. She worked from a desk on her laptop and had been doing it for a couple of months.
“It’s only a quiet street so she would let them play outside.
“I think they had a hula-hoop and dolly’s pushchair. I’m sure she would have been inside.”
A resident from the area told the Telegraph: “I didn’t see what happened, but we were told they (police) were looking for footage of a man running away.”
Taxi driver Jonathan Newton, 55, said: “We are a close knit community here and the town is rocked to the core by this tragedy.
“She was just a little girl, how could anyone do this to a nine-year-old? It’s the most shocking tragedy to ever befall our little town.
“I’m just speechless.”
East Area Commander Chief Superintendent Kate Anderson previously said: “Our thoughts continue to be with Lilia’s family and friends.
“If any members of the public have information that might assist, please call 101 quoting incident 419 of 28th July, or they can report anonymously via Crimestoppers.”
A spokesperson for Lincolnshire Police added: “We can now confirm the identity of the nine-year-old girl who sadly died in Boston yesterday as Lilia Valutyte.
“She died on Fountain Lane, as a result of what we believe to be a stab wound.”