The Iraqi judiciary announced on Tuesday the launch of a probe in the voice recordings that have been attributed to former Prime Minister Nouri al-Maliki.
The Supreme Judicial Council said it had received a request from the general prosecution to take legal measures over the recordings.
In the recordings, Maliki is heard threatening violence against Sadrist movement leader, cleric Moqtada al-Sadr. He is also very critical of other major political figures and describes the Popular Mobilization Forces as "cowards."
Iraq has been swept up in the recordings for days.
They were obtained by Iraqi journalist Ali Fadhel, who resides in the United States. In a tweet, he revealed that the recordings are of "an hour-long meeting between Maliki and others." He hasn’t disclosed how he obtained them.
Fadhel has been releasing about a minute of the recordings a day.
The latest, released on Tuesday, have Maliki discussing partnering up with an armed Shiite faction to wage a confrontation with the Sadrist movement.
He is heard having discussions with representatives of a largely unknown Shiite faction, the "Ummet al-Akhyar", whose religious reference is known as "Ayatollah al-Mirza".
One of the members of the group, "Abu Hassan", was heard offering allegiance to Maliki to "shed blood".
Sadr has already demanded that Maliki turn himself over to the judiciary and quit political life.
Maliki has dismissed the recordings as fakes.