A woman accused of stabbing a 13-year-old girl to death in a Doncaster park on Valentine's Day has a "troubled history" and has spent time in a psychiatric hospital, a court has heard.
Hannah Bonser, 26, went on trial accused of murdering Casey Kearney, who was found injured in Elmfield Park.
"Hannah Bonser is a woman with a troubled history, who was in regular contact with outreach workers at Rethink - which is a service which assists those in Doncaster with mental health difficulties. In October 2011 she had spent a short time in a psychiatric hospital in Doncaster."
Bonser, of Cusworth House, Doncaster, denies murder. Three days before Casey's death, Bonser told a friend she was going to kill her ex-boyfriend and threatened to "get anyone else who crossed her", the court heard.
In the morning of Casey's death, Bonser bought two kitchen knives, the jury heard.
"It cannot be known why Hannah Bonser went to the park that afternoon. She later declined to answer police questions and she now claims to have no memory of what she did."
Investigation underway into Hannah Bonser's contact with a range of services prior to her random killing of schoolgirl Casey Kearney
Hannah Bonser has been jailed for life after she was found guilty of murdering schoolgirl Casey Kearney at Sheffield Crown Court
Jury hears claims a woman accused of stabbing a teenager in a Doncaster park told a charity worker that 'she'd done something silly.'