A gang broke into the Toby Carvery yesterday wielding what is believed to have been an axe.
Police say four people entered the restaurant in Braywick Road, Maidenhead, through a fire exit at about 1.20am and ordered staff to leave.
They conducted a search, before leaving in two vehicles, believed to be a silver Subaru Impreza and a silver Subaru estate car.
No-one was injured and no cash was stolen.
The four offenders all had their faces covered but are believed to be male.
Three wore dark clothing and one wore a light grey tracksuit with a dark t-shirt over the top.
Contact DC Dave King on 101 or Crimestoppers anonymously on 0800 555111.
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