"This was abrazen robbery, and appears to have been well planned and thought through.Fortunately no one was injured. The store was very busy and this will have beena shocking thing for people to witness.
"I'd like to thank those members of the public who stepped in and detainedour two suspects. Their quick thinking and brave actions have helped ourinvestigation."
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"All it takes is for somebody to see me - and I could just die, just like that. I could want to go to the shop and not come home."
Before the killing, Peters searched the internet for "serial killers", "treatment of child killers in prison" and "premeditated murder".
Arriva Rail North, Greater Anglia and South Western Railway are all affected.