The two journalists were held over the weekend amid a government clampdown on the free press.
311,083 have fled Burundi's violence, which has left up to 2,000 people dead since April 2015.
AU President Deby's stance on President Nkurunziza's mandate 'misrepresents' crisis, say opponents
Envoy will also discuss International Criminal Court withdrawal as pressure mounts on Bujumbura
EXCLUSIVE: Diplomat says world is failing to move on to the final phase of prevention of crimes against humanity
Opposition coalition says ICC exit should not give authorities 'a free band to continue committing crimes'.
Bernard Maingain says it shows a 'wave of panic sweeping among leaders' over investigation into killings.
EU suspended funding to the African country over rampant rights abuses and unwillingness to quell crisis.
ICC opened preliminary examination into abuses that may amount to crimes against humanity.
UN report names suspects and says government used security apparatus to carry out possible crimes against humanity.
Talks to end Burundi crisis which has rocked the country for around 18 months have stalled.
Iwacu journalist Jean Bigirimana was allegedly forcibly disappeared in Burundi on 22 July.
IBTimes UK speaks to Pierre-Claver Mbonimpa who alleged 14 mass graves have been identified.
Burundi closes border with Rwanda, whom it accuses of arming Burundian rebels, as diplomatic relations worsen.
IBTimes UK speaks to Iwacu founder-director Antoine Kaburahe about the investigation into Bigirimana's disappearance.
President Pierre Nkurunziza's CNDD-FDD is being 'militarised' as a solution to conflict is still not found
Defections come amid fears a crackdown by the authorities has particularly targeted young Tutsi officers.
One body found beheaded during search for missing journalist Jean Bigirimana – allegedly abducted on 22 July.
EXCLUSIVE: IBTimes UK speaks to lawyer Dieudonné Bashirahishize under threat for speaking to UN watchdog.
Human rights experts urge government to ensure four men will not face punishment.
Burundi government says French-led UN resolution authorising the force was made without its consent.
IBTimes UK speaks to Iwacu director Antoine Kaburahe about missing reporter and father of two