Three people were arrested at a home on West 20th in The Dalles as the result of a two month drug investigation. A Mid-Columbia Interagency Narcotics Task Force spokesman said Wednesday the search warrant was served on March 5 as a result of the probe into possession and delivery of heroin, methamphetamine, and heroin. One man and two women in the house at the time all were arrested on distribution and possession of a controlled substance charges, while one was also charged with frequenting a place where narcotics are sold. The investigation is on-going, and anyone with information is asked to call the MINT tip line at 541-296-1885.