Several reports of loud rumbling noises, distant bangs and houses shaking are being made by residents in the Skegness and Mablethorpe areas.
Some have taken to Facebook speculating it could be anything from an earthquake - to an invasion of Transformer robots.
But rest-assured, Lincolnshire Police have said people need not to be concerned.
In a statement, a police spokesman said: “Please be reassured, this is connected to the RAF exercising at Theddlethorpe Range.”
One Facebook user commented: “Omg shaking my whole house and my dog is scared and shaking - and so was I.”
Another commented to the police: “Wish they told us in advance. Scared pets and people all the way to skegness.”