He said an electoral officer in charge of the area sabotaged INEC’s preparations by allegedly withholding materials rather than distributing them.
Besides, he said the result sheets, which differ according to units, were jumbled up.
The commission had to take time to rectify the mix up, which resulted in the delays experienced, he said.
Jega said he suspected that the officer was induced by someone who wanted to subvert the process, adding that the alleged culprit has been handed over to the police for prosecution.
The INEC, chairman, who spoke on AIT during a programme on the election, which was monitored in Awka, said every effort would be made to get to the root of the alleged sabotage.
He said: “We made all the preparations and decentralised the process of distribution of materials in order to ensure that they get to the polling units in time for the commencement of the election. That was before Saturday.
“Unfortunately and regrettably – we are humans. We can do all the preparations, but if people are determined to subvert the process, one way or the other they will subvert it.
“So, they used our staff. I think we should be very careful when we have a staff of about 12,000 in INEC, when one person has committed an offence and then you use it to generalise or condemn everybody in INEC.
“Our Electoral Officer in charge of Idemili North Local Government, for inexplicable reasons, messed up the distribution of ballot box papers and result sheets. That was the cause of the delay in the distribution of materials in Idemili.
“All materials were to have been distributed by Friday evening, but for some odd reasons, they made sure that they held onto some of the result sheets, and they also gave wrong result sheets to different polling units.
“I assured the stakeholders when we met in Awka that materials must get to the polling units before commencement of election.
“So, when we discovered at about 1am that there was this mix-up, and we tried to reach the Electoral Officer and the supervisor and there was confusion, and we knew something was fishy, we said there would be no deployment until we sorted out the problem.
“As I speak, we have handed over the Electoral Officer to the police because clearly what he did is a sabotage of the electoral process, including the Local Government supervisor.
“It took us until about 1pm to be able to sort out what they had jumbled up. We communicated with the community as at 1pm that we were ready to distribute to all the other wards, and materials were distributed.”
Jega said INEC officials consulted with the community before rescheduling the election, which the All Progressives Congress (APC) rejected.