Labour leadership candidates say they want a clean contest and are trying to rein in anonymous twitter accounts set up by supporters (internet trolls).
Online messages have ranged from harmless to misleading, to downright nasty.
Grant Robertson said he messaged the account supporting his bid and asked the person behind it to stop tweeting - which they did.
The account supporting the bid by Shane Jones mostly undermines the other two candidates.
And the one supporting David Cunliffe has been the most active and the most negative.
Mr Cunliffe said the account has nothing to do with his campaign.