"The legal department in the board is having a look at Zulqarnain's message on his facebook account and his subsequent comments in the media on Kamran Akmal," a Pakistan Cricket Board source told PTI.
"In all likelihood, the board will be issuing a show cause notice to Haider through its disciplinary committee to explain his position even though he is not a contracted player with them," he said.
The source pointed out that when the board removed Haider's ban and allowed him to resume playing domestic cricket he was also put on a probation watchlist.
The PCB had also arranged for a sports psychologist to hold counselling sessions with Haider last month.
Umar Akmal, Ahmed Shahzad and Muhammad Aamir were the other players selected for the counselling sessions with Dr Maqbool Babri.
Haider in his latest outburst on Wednesday threatened to make startling revelations about corruption in the Pakistan team after claiming that Kamran was not cleared by the ICC for selection in the national team. MORE