A GUNMAN is on the run after terrorising families and young workers at a Sydney McDonalds overnight.
An armed man held up the store at Merrylands about 8.15pm, threatened customers, assaulted staff and fled with cash and a handbag.
Two teen cashiers, a 16-year-old girl and 15-year-old boy, were hit in the head when the robber jumped the counter.
He then grabbed a 24-year-old female manager by the neck and forced her head into a wall before ordering her to open the safe.
The injured boy was taken to Westmead hospital and treated for a cut to his head.
Detectives are searching for a man of Mediterranean/Middle Eastern appearance who is between 160-170cm tall with a slim, athletic build.
He was last seen wearing a red, hooded jumper, dark track pants and runners.
Anyone with information can phone Crime Stoppers on 1800 333 000.
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