0644 GMT July 17, 2018
According to the Seismological Center of the Geophysics Institute of Tehran University, the tremor occurred at 5:43 hours local time (1:13 GMT) in an area located at the depth of 8km underground, IRNA reported.
No report on possible damage to life or properties has been released yet.
The epicenter of the quake was registered at 12km from Sisakht, 17km from Yasouj and 24km from Chitab.
Another earthquake measuring 5.1 on the Richter scale shook Sisakht in southwestern Province of Kohgilouyeh-Boyerahmad on May 2.
Iran sits on major fault lines and is prone to near-daily earthquakes. Also on Sunday, a 5.3-Richter quake rattled the area, as result of which 54 people were injured.