The four-time former MP, his wife Navjot Kaur Sidhu and their son Karan Sidhu entered the Mata Saroop Rani College premises along with their cavalcade of three private luxury cars, sources said.
Mr Sidhu is contesting the Assembly polls from Amritsar East seat on Congress ticket.
As per Election Commission guidelines, nobody could move in the polling booth premises along with their vehicles, except handicapped or physically challenged persons.
Mr Sidhu and his family, who were moving in three different SUV cars, were stopped at the main entrance gate of the polling booth by the paramilitary forces. But he gained entry by saying that he was carrying special permission to go inside along with the vehicles.
"We are verifying the facts by checking the CCTV footage. If legitimate proof proves that his vehicles were found inside the premises, action will be initiated as per the guidelines of Election Commission of India. Sidhu was not permitted to go there along with his vehicles," Mr Garg said.
Mr Sidhu's residence falls in the Amritsar North constituency.
His wife Navjot Kaur had won the elections from Amritsar East during the previous assembly polls on BJP ticket.
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