LOWELL -- City police are investigated the armed robbery of a Gorham Street convenience store that was held up at knifepoint Saturday night by a man who had a scarf wrapped around his face.

Police were called to Lowell Mini Mart, 1344 Gorham St., at 7:40 p.m. after a clerk called 911 and reported she was just robbed by a man with a "large knife."

The suspect wore a black hooded sweatshirt, gray sweatpants and had a scarf covering his face. The clerk believed the suspect's voice sounded Hispanic, according to police radio broadcasts.

Officers requested assistance from a canine unit, so Chelmsford Officer Dave Leo and his canine partner Flacko responded and tracked the suspect a short distance up Bowden Street before the scent disappeared.

Anyone with information is asked to call Lowell police at 978-937-3200 or Crimestoppers at 978-459-TIPS (8477).

Tipsters can remain anonymous, but can receive up to $1,000 for information leading to an arrest.

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