Authorities investigating the disappearance of a gas station night clerk in West Michigan say they're continuing to work around the clock on the case.
Norton Shores Police Chief Dan Shaw says investigators on Sunday conducted interviews and investigated some "high-priority" tips.
Jessica Heeringa hasn't been seen since April 26 when she was working at an Exxon Mobil gas station in Norton Shores, 40 miles northwest of Grand Rapids.
Many people have been ruled out as having a role in the 25-year-old mother's disappearance, including her fiance and a former boyfriend. Police have released surveillance footage of a van that could be related to the suspected abduction, as well as a sketch of a man sought for questioning.
Heeringa's purse, car and coat were left at the gas station.
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