The cause of the fire remained unknown, and continued to burn in some of the warehouses belonging to the Supreme Electoral Committee, located in the center of Baghdad, but no further details were available.
Salim al-Jabouri, who lost his seat in May's election, said the fire was "a deliberate act, a planned crime, aimed at hiding instances of fraud and manipulation of votes".
Haidar al-Abadi condemned the burning of the election warehouse in Baghdad as part of a plot against the nation and its democracy.
"Burning election warehouses.is a plot to harm the nation and its democracy", Abadi, whose coalition faltered in the polls by finishing third, said in a statement on Sunday.
He said the government would "take all necessary measures and strike with an iron fist against those who undermine Iraq's security".
"It is possible there were also some ballot boxes in the warehouse that caught fire", said Iraqi Maj.
An alliance led by influential Shiite cleric Moqtada al-Sadr - an outspoken opponent of the U.S. and Iran - won the most seats, dealing a political blow to al-Abadi.
The complaints put IHEC under pressure, as the electoral commission has not carried out manual recount of many ballot boxes and depended only on the electronic count of the votes.
"It is not an ideal situation for Iran and they might support a redo, but actually a recount might implicate them if the allegations in the north are correct". He scored a surprise victory in the election, with his followers emerging as the largest political bloc in a highly fractured parliament.
Many Iraqi parties, especially in the semi-autonomous region of Kurdistan and the disputed areas, including Kirkuk province, have complained about alleged irregularities and forgery in the parliamentary election.
Abadi, whose electoral alliance came third in the election, had said that a government investigation had found serious violations and blamed Iraq's independent elections commission for a lot of them.
The election's votes were initially counted electronically, and parliament has since called for a full recount.
Certain parties are trying to drag Iraq into civil war, Sadr said, adding that he would not participate in one.
"The room where voting machines and other election equipment were stored was destroyed by the fire", Imed Jamil, an electoral commission official for Al-Russafa, told AFP.
"We call for the election to be repeated", he said. Two legal experts and an official source at the elections commission confirmed that every vote has been stored electronically.
"Nothing is known, but there are people who would not want the votes to be recounted because it would prove their fraud or they could loose even more votes", federal intelligence officer Abo Musa said.