BALTIMORE (AP) — A Baltimore grand jury has returned indictments against 27 people allegedly involved in three heroin distribution networks.

The Baltimore State’s Attorney’s Office said Wednesday that the months-long investigation targeted neighborhoods in West Baltimore where violence and drugs are rampant.

Authorities say 18 of the 27 defendants are in police custody, including the alleged supplier of the networks.

Three drug distribution enterprises were targeted. Of the 18 who have been arrested, four were charged in connection with the Lynnbrook Group, three were charged as part of the Orem-Parkwood Group, and 11 were charged as part of the Woodbrook-Gwynns Falls Group.

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