A stranded bus had to be towed away by Coastguard teams after it was found on Cleethorpes beach.
Teams from Cleethorpes Coastguard and HM Coastguard Donna Nook Rescue Team were called to the scene at around 2.44am on Friday, after the vehicle was discovered next to the pier.
It was established that no-one was inside the single-decker bus, and steps are now being taken to establish how it got there, Humberside Police said.
Coastguard teams carried out searches along the beach for anyone who might have been on board, but no-one was found on the shore or in the water.
"Due to the fact that there was also a risk of pollution from oil and diesel from the bus, it was towed out of the water, back on to the roadside," Cleethorpes Coastguard said.
A spokeswoman for Humberside Police said on Friday: "Police assisted the Coastguard in recovering a bus which was located on the beach at Cleethorpes overnight.
"Nobody was in the vehicle, which has now been recovered, and inquiries are under way to establish the circumstances leading to the single- decker, red-and-white bus being on the beach."