DUP councillor Luke Poots has called on the Alliance Party to condemn threats made against him in the same way it has hit out at racist abuse suffered by party leader Anna Lo.
Mr Poots, son of health minister Edwin Poots, said he has been subjected to threatening letters and phone calls and been harassed online.
The Lisburn councillor said members of the Alliance Party had not been behind abusive messages on social media but had responded to comments made online rather than condemned them.
Mr Poots said he opposed the abuse levelled at Ms Lo in recent days and her party should show him the same support.
In response the Alliance Party said it "abhors any form of bullying or intimidation".
"We treat this matter very seriously. We were made aware of the allegations on Thursday evening on social media.
"We are writing to Luke Poots seeking clarification as to which members of the party he is alleging were involved in such behaviour as Alliance will not tolerate any party member being involved in such activity.
"Further, we have contacted the PSNI to clarify whether any complaint has been received to this effect from Luke Poots and whether the party can be of any assistance in any related investigation. We are awaiting their response."