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SAN ANTONIO (CBSDFW.COM/AP) — A San Antonio woman thought she had won a contest after finding a green bag inside her granola bar package. It wasn’t a prize — it was cocaine.

San Antonio police are investigating how the packet of cocaine ended up inside a wrapped Nature Valley granola bar.

Cynthia Rodriguez says she was eating the bar when a small, green bag emblazoned with dollar signs fell out. Rodriguez contacted manufacturer General Mills Inc., thinking she had won a prize. Company officials told her to call the police.

Rodriguez contacted police March 18 and investigators determined the bag contained cocaine.

Sgt. Javier Salazar says authorities are trying to determine how the package got inside the granola bar wrapper.

A General Mills spokesman said Thursday that the Minneapolis-based company is confident the cocaine wasn’t packaged with the bar at a company facility. Mike Siemienas declined to say where the bar was produced.

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