The Outrigger Motel in Grove received serious damage in a Friday-evening fire.
It is now reported the Oklahoma State Fire Marshall will be investigating the blaze.
Firefighters reportedly were called to the longtime lake-area motel around 8 Friday evening.
The cause has yet to be determined.
Several fire departments responded to the blaze which took several hours to contain.
For a time, SH 59, the main east-to-west highway artery into Grove had to be closed.
There were no injuries to motel patrons or first responders.