Of this, 6 percent names are excess and 7 percent duplicate, while at least 2.5 percent eligible voters are missing in the list, according to the second NDI survey on the integrity of the voter list.

The report has been prepared on the basis of checking 22,000 names, interviews of 11,000 individuals in 37 villages of Dhaka, Rajshahi, Chittagong-Sylhet, and Barisal-Khulna regions. NDI Residential Director Owen Lippert presented the report at a press conference at a city hotel.

With improvements, the voter list can be part of a credible election, but an accumulation of risk factors including excess ballots and clerical error could lead to a situation where a potentially acceptable election result may not be perceived as credible, the Washington-based institute said.

Correcting the voter list is possible in two months, provided the political parties and the civil society of the country cooperate in the process, Lippert said.

Terming the list "only one important part" of the election process, the NDI chief in Bangladesh said responsibility for a credible election lies not only with the Election Commission, but also with the caretaker government, public administration, political parties and ultimately the citizens.

The supplement list of new voters often did not match the existing voter list, Lippert said. Suggesting double checking, he said, "Improved matching of supplemental and existing voter lists will reduce the possibility of confusion on election day."

NDI Project Manager Najia Khogyani-Hashemee identified migration, incorrect registration, death, and registering names of unknown or under-age persons as the reasons for excess names in the electoral roll.

She said rural centres are more prone to error and Rajshahi region has the highest level of error.

According to the NDI report, duplications are the result of registering names of the same persons at two places while names were missed because of the voters' not being present at the time of registration or intimidation or deliberate dropping.

NDI Senior Consultant Dr Mohammed Yusuf and Communications Consultant Shadia Syed were present at the press conference.

In his reaction to the report, Awami League (AL) leader Saber Hossain Chowdhury said the AL has been alleging that 1.4 crore voters in the updated voter list are fake and the NDI report has almost proved it.

The additional ballot papers for these excess voters are more likely to be abused in the election, he said.

Former foreign affairs adviser Reaz Rahman said the mistakes in the updated voter list are "inherited". "It should be checked if the mistakes are natural," he told journalists.