SIOUX FALLS, S.D. (KELO AM) - Sioux Falls police say an alert Winnelson employee noticed a discarded, one-pot, meth lab along the road on South Van Epps Avenue, which led to the arrests of four suspects on felony drug charges Thursday. Officer Sam Clemens says the discovery turned investigator's attention to a house on East 12th Street. Clemens says police found litium batteries that had been cut in half, exposing an ingredient used in meth making, behind the house of 1315 East 12th Street. 21-year-old Amber Counterman of of Sioux Falls, 33-year-old Tyler Hausten and 19-year-old Abigail Shelton, both transients, are charged with possession of meth. 23-year-old Jonathon Julson of Sioux Falls is charged with possession of marijuana with intent to distribute. Police more arrests are likely.