"A case has been lodged against Gadkari, Singh and dozen other BJP leaders for violation of the model code of conduct at Suryawan Police Station," Deputy Returning Officer Uma Kant Tripathi said.
He said the BJP candidate had taken permission to organise a meeting at Abholi block between 11 am and 5 pm.
However, Gadkari's chopper landed at 5.30 pm and the former BJP chief was stopped from proceeding to the venue of the meeting by police.
District Returning Officer Ranveer Prasad said a thorough probe into the matter was on.