A 14-year-old girl who died following a hit-and-run collision which also left a 12-year-old seriously injured has been described as "a beautiful, smart, young lady with such a kind heart".
Police are investigating whether Jasmyn Chan died as she tried to help her younger friend as they crossed a road in Sheffield on the way back from a park.
South Yorkshire Police officers have made a direct appeal to the car driver to come forward following the collision on Normanton Hill, at 9.20pm yesterday.
Jasmyn - known as Jazzy - was crossing the road with four friends when the crash happened, friends laying flowers at the scene said.
Three of the group of boys and girls, who had been in Richmond Park, made it to other side but the car was in collision with Jasmyn and the 12-year-old girl, who has not been named.
Jasmyn suffered fatal injuries and the other girl was taken to hospital where she is being treated for serious injuries.
Dozens of floral tributes to the teenager have been laid around a signpost by the road and steady stream of friends came to the spot during the day.
Some of the youngsters sat together around the flowers in an impromptu vigil, many in tears.
They said they had been told Jasmyn had gone to aid of the younger girl when they were both hit by the vehicle and police are understood to be investigating this possibility.
"In school, I never saw you without a smile on your face," one message left with flowers read.
"You brightened up a room just by your presence. You were just a beautiful, smart, young lady with such a kind heart."
Another said: "I can't believe you've been taken from us"
Another friend said on Twitter: "RIP Jazzy Chan. You were such a lovely, hilarious person and you definitely didn't deserve this. We will all miss you!"
The accident happened at the bottom of a long, straight hill on the 30mph road. Skid marks stretching for about 70m could clearly be seen on the road surface today.
Chief Inspector Stuart Walne said: "Jasmyn was an active, friendly girl who was very giving.
"This situation is even more upsetting as the driver didn't stop at the scene.
"The driver may not have intended to cause this collision nor are they likely to have been aware of the extent of the injuries they caused last night.
"However I would urge them to think about the impact on Jasmyn's family, friends and community and please come forward.
"Investigating officers are working on a number of leads and people have been giving us information."
Officers have said the car has been described as small and dark-coloured, possibly green, and maybe a Volkswagen or a Honda. Mr Walne said it will have damage to the front and the driver's offside.
Jasmyn lived with her parents and younger sister just a few hundred yards from where the crash happened. She was a student at Birley Community College, in Sheffield.