One of country music's biggest stars is playing a free concert tonight at the Grizzly Rose in Denver.

This morning, Blake Shelton posted the following message on Twitter, "Denver Colorado...You!!! Grizzly Rose. Doors at 6 pm. First come, first serve".

Shelton's twitter post has been officially confirmed by the venue. Shelton played another "surprise" free concert at a nightclub in Kansas City last night.