"Mewat district of Gurgaon parliamentary constituency is a sensitive zone all through the year and especially so during election time. This has been further compounded by lack luster performance of the district administration," Singh said in his letter to the Returning Officer.
"The question now arises in my mind is whether this lack of performance was motivated by ulterior considerations or was an inherent disability in its genetic make up," he said.
He added that the EC should ensure that proper care is taken during the counting.
AAP candidate from the seat, Yogender Yadav had also alleged rigging in the Mewat area.
Singh, a former Union Minister and an old Congress hand in Haryana, had accused Sonia Gandhi's son-in-law Robert Vadra for alleged irregularities in land dealings in Gurgaon.
He had also lashed out at Chief Minister Bhupinder Singh Hooda over the same and had quit the party to join the BJP.