A Kitchener man, 26, is in critical condition after an early morning fight outside the Stampede Corral, police say.

Waterloo Regional Police spokesperson Olaf Heinzel said a fight broke out between a group of men in the parking lot of the country and western bar shortly after 2:30 a.m. Thursday.

Police were called to the scene where they found the man unconscious.

"The male was initially transported by ambulance to a local hospital but due to his injuries has been subsequently transported to Hamilton for further treatment," said Heinzel.

Police are still investigating exactly what led to the assault and how many people were involved.

Heinzel says police have one man in custody, but formal charges have not yet been laid.