passage: (CNN) -- Oklahoma health officials said Friday they are searching for the source of a rare form of E. coli that has killed one person and sickened 116 others in the northeastern part of the state. The subtype of bacteria -- called E. coli 0111 -- is "not normally found in this form of outbreak," said Leslea Bennett-Webb, director of communication for the Oklahoma State Department of Health. More than 50 people have been hospitalized and nine people -- six of them children -- have been placed on dialysis, she said. She said the federal Centers for Disease Control and Prevention in Atlanta, Georgia, helped state officials determine the subtype, but said the cause of the outbreak remains unknown.
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  1 person dead, 116 ill in northeastern part of the state
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  Focus of investigation is restaurant in Locust Grove, Oklahoma
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  Officials say this form of E. coli is "not normally found in this form of outbreak"
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  Officials say outbreak appears to be abating
query: The Oklahoma @placeholder will analyze them and compare them with samples taken from victims, she said.
entities: Atlanta CNN Centers for Disease Control and Prevention E. coli Georgia Leslea Bennett-Webb Locust Grove Oklahoma Oklahoma State Department of Health