The fire, which broke out at the stadium on Wednesday last week, is thought to have been started deliberately.
It started in the seating area near to the running track before spreading to the main building.
Hundreds of children were in the building at the time but were led to safety as three fire crews were able to bring the blaze under control.
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Chief Inspector Helen Brear of West Yorkshire Police posted the photograph on Twitter today, seeking the public's assistance in helping with the arson investigation.
She said: "This is my little girl Bella been taken out of Thornes park stadium along with 100 other young people, after it was set on fire.
"Please can I seek your help in helping my previous NPT team. Thank you.
"Call Crimestoppers T. 0800555111
"Email [email protected]"