Saday and his supporters were travelling in a four-wheeler after putting up banners and posters seeking votes when police intercepted them at Bhagwanpur Chowk and found he had not obtained pass from the election authorities for vehicle, Raj Nagar police station in-charge Satyendra Kumar said.
An FIR was promptly lodged against the SP candidate for model code violation and his vehicle was impounded, he said.
Saday, however, feigned ignorance about model code of conduct being in place for the bypoll.