Investigators are at the scene of a crash in which four people died when two aircraft collided mid-air near Grasmere in Gauteng, the South African Civil Aviation Authority (Sacaa) said on Tuesday.
Members of its Accident and Incident Investigations Division were sent to the area after the collision on Monday night.
"The investigation team is at the scene, and the evidence collection phase has thus begun. This phase will help in defining the size, scope and anticipated time frame of the investigation," Sacaa spokesperson Kabelo Ledwaba said.
"The purpose of an aircraft accident investigation is to establish the cause or the probable cause of an accident and, if necessary, to issue safety recommendation(s) that will help avoid the recurrence of accidents as a result of the same cause(s)," he said.
Ledwaba said a preliminary report would be issued within 30 days.
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