A man at the head of a criminal enterprise that used a truck to ship narcotics from California to Michigan is behind bars, charged with conspiracy to distribute heroin and cocaine, federal court records show.

Alex Castro, 37, was indicted this week for his role in a major drug conspiracy that trucked hundreds of pounds of cocaine and heroin into Grand Rapids. Investigators say an estimated 13 pounds of cocaine and heroin was shipped to West Michigan every two to three weeks for more than a year.

Related: California drug connection trucked cocaine and heroin to Grand Rapids

The drug conspiracy involved at least 18 people and ran from 2016 through September of this year, according to records in U.S. District Court in Grand Rapids. Castro is identified as the California-based source for the narcotics.

He has a lengthy criminal past and is identified as an associate of the Black Angels gang, described in court records as a criminal enterprise focused on narcotics trafficking in southern California.

Officials with the Drug Enforcement Administration in Los Angeles say Castro is one of more than four dozen people indicted as part of a Mexican Mafia prison gang conspiracy responsible for numerous violent crimes along with heroin and methamphetamine trafficking.

He was sentenced in Oct. 2011 to nearly three years in federal prison.

Castro was linked to the California to Michigan drug ring based on intercepted phone conversations, federal court records show. Castro is alleged to have been the person who kept Yusef Phillips – described as one of the Michigan leaders – supplied in narcotics.

Castro’s federal probation officer recognized Castro as the speaker in phone calls to Phillips, including a conversation in which he discussed sending Phillips multiple kilograms of cocaine and heroin, court records show.

Castro was arrested last Friday in Los Angeles. In a federal indictment filed Wednesday, Sept. 13, Castro is charged with conspiracy to distribute heroin and cocaine from about 2016 through Sept. 1, 2017. If convicted, he faces a minimum of 20 years and up to life in prison.

Castro remains locked up in California; he is fighting extradition to Michigan. A federal identity hearing is scheduled for Oct. 10 in Los Angeles.

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