The UK teenager accused of killing three young girls at a children's dance event will appear in court tomorrow, now on a terrorism charge. 

England's Merseyside Police yesterday announced they'd discovered a bio-toxin and al Qaeda documents in the 18 year old's home following the July mass-stabbing. 

UK Correspondent Gavin Grey told Ryan Bridge it's a shock twist in the devastating case. 

He says despite the terror charge, counter-terrorism Police say the incident isn't classified a terrorist incident. 

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