TUCSON, Ariz. (AP) -- A nearly yearlong investigation into dog fighting led to the serving of several warrants Tuesday in Tucson and elsewhere in Pima County.

The Pima County Sheriff's Department said in a statement that warrants were served on several alleged dog fighting organizations and that arrests were expected.

The raids stemmed from an investigation started after the department received information from the Humane Society in March 2007 that a possible dog fighting ring existed in the Tucson area.

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