The FBI in Las Vegas is offering up to $10,000 for information about five armed robbers accused of beating a security guard with a gun during a smash-and-grab robbery at a Rolex store on the Las Vegas Strip.

A bureau spokeswoman said Tuesday she couldn't provide details about why a reward was posted in the late May 19 robbery at the store in the Forum Shops at Caesars Palace.

The FBI says the robbers may have driven away in a black Chevrolet Camaro and a gray Lexus RX300.

Police said the suspects broke glass display cases and swept up a number of watches. The value of the items wasn't made public.

Police said the guard was taken to a hospital with head injuries that weren't believed to be life-threatening.

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