The ICAC on Thursday said three more people had been arrested on suspicion of inciting people not to vote, or to cast invalid ballots, in this month's Legco elections.
The two men and one woman, aged between 22 and 57, are accused of sharing an online post which allegedly asked members of the public to cast blank votes.
Several mobile phones were confiscated in the ICAC operation.
All of the suspects were released on bail, pending further investigation.
The anti-graft body made three arrests last month and was granted arrest warrants for former Democratic Party legislator Ted Hui and a former district councillor in connection with similar alleged offences.