He rejected the declaration of David Mark as winner by the Independent National Electoral Commission (INEC).
Abounu, who addressed reporters in Makurdi, alleged that gunmen, allegedly recruited by the Peoples Democratic Party (PDP), attacked the All Progressive Congress (APC) supporters.
He rejected the result, saying 29,000 votes were cancelled, while Mark won with a difference of 12,000.
Abounu said: “By law, INEC should have declared the election inconclusive as it did in Kogi and Bayelsa.”
He said they would take the matter to the tribunal.
Accredited observer groups under the Credible Leadership and Citizens Awareness (CCLCA) have alleged that the rerun was characterised by ballot snatching.
Director-General of the groups Dr. Gabriel Nwambu, at a briefing in Abuja yesterday, said the election was held under best practices, but was characterised by irregularities.
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