Published: Jul 25, 2011 7:24 PM EDT
Updated: Jul 25, 2011 6:25 PM EDT

OSLO, Norway (AP) - Norway's police security service says it was alerted in March to a suspicious chemical purchase by the man who set off a bomb in the capital last week, but it didn't have enough evidence to investigate further.
    
Janne Kristiansen, the chief of PST, said Monday that Anders Behring Breivik paid 120 kroner ($22) for an undisclosed product from a Polish chemical firm.
    
She told national broadcaster NRK that the purchase set off an alert because the company was already under scrutiny, but the transaction was legal and PST would have needed additional information to investigate further.
    
In his manifesto, Breivik describes a purchase of sodium nitrite from Poland, saying he "was concerned about customs seizing the package." It was not clear if that was the purchase that was flagged.

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