The attack was carried out by armed assailants, and explosions and gunfire were heard from the scene shortly afterward.
Security forces and emergency responders quickly arrived at the site, evacuating wounded individuals and courthouse staff.
Ambulances transported the injured to local medical centers, while police forces secured the surrounding area and entered the building.
The extremist terror group Jaish al-Adl claimed responsibility for the attack through an online statement.
Initial reports suggest the possibility of a suicide bomber, although the exact cause of the explosion has not been confirmed.
According to security sources, three attackers were killed during the assault, which began with gunfire directed at the courthouse and later extended indiscriminately to nearby civilians. Damage was also reported to private property.
Investigations are ongoing to assess the full scope of the incident.
Zahedan, the capital of Sistan and Baluchestan Province, has experienced periodic unrest and militant attacks in recent years.
