13 year-old Casey Kearney died on Valentines' Day after she was stabbed in Elmfield Park in Doncaster.
Police want people who were seen near the park just after 1pm that day to contact them.
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Former Hull FC star Tom Briscoe scored five tries to see Leeds Rhinos retain the Challenge cup with a record 50-0 win over Hull KR.
Labour leadership candidate says Britain playing its role in the migrant crisis would help Cameron secure the promised reforms in Brussels.
The Rhinos lead Hull KR 16-0 at halftime in the Challenge Cup final.