The elections watchdog said on Friday that it's found some two thousand votes that should have been counted at last month's District Council elections – but were missed after a glitch in the electronic poll register system.

The chairman of the Electoral Affairs Commission, David Lok, said the extra votes would not have changed the result in any of the constituencies.

He said the deviation resulted from a switch to manual counting after the glitch.

After a recalculation, the final turnout rate for the polls was at 27.59 percent, 0.05 percentage points higher than what was previously announced.

Lok said because the vote counting process was all recorded on video, he's not concerned that candidates would mount a legal challenge over the results.

"The human error took place under a very tight deadline. On that day everyone paid so much attention on the turnout rate. Our staff was under tremendous pressure. So I think the mistake is actually understandable," he said at a press conference.

"But most importantly, I must stress, we didn't affect the election results."

As to what caused the computer glitch, the commission said the electronic registrar’s server had been overloaded as a result of system design flaws.

Bernard Man, a commission member who heads a task force probing the issue, said the problem stemmed from the commission's technicians making changes to the system's design before the polls without conducting comprehensive loading tests.

In an intermediate report submitted to the Chief Executive, Man said his group has ruled out the possibility of an outside attack, saying there was no indication of log-in attempts by external devices.

When asked who should be held accountable for the mishaps, he said that's something for the administration to consider.

Constitutional affairs minister Erick Tsang, for his part, told RTHK that it was very regrettable that the glitch and vote-counting error took place.

He apologised to affected voters on behalf of the government, and said officials will take all necessary measures to avoid a repeat of the incident.