Hackers briefly disrupted the online voter registration process for Tunisia's parliamentary and presidential polls later this year, the electoral commission said on Thursday.

The commission announced on its Facebook page that registration on the Internet or by SMS was temporarily suspended following "an aggressive attack from a group of electronic hackers seeking to prevent citizens from registering."

The body charged with organising the vote, known by its acronym Isie, said the whole team was working on the problem "to allow registration to resume in the shortest possible time."

It later said the online registration process had resumed, while warning that "the hacking attacks are still going on."

Voters enrolling at designated offices were not affected.

The registration process, which began on June 23 and is due to finish on July 22, has so far seen just over 100,000 people added to the electoral list.

About eight million Tunisians are eligible to vote in the upcoming polls, but only half that number registered in 2011 for the first election after the revolution that toppled a decades-old dictatorship and sparked similar uprisings across the region.

To encourage participation this time, Isie made it possible to register on the Internet or by SMS, as well as at by turning up at designated offices.

After months of political wrangling, Tunisia's parliament last month approved October 26 as the date for the legislative election and November 23 for a first round of the presidential poll.