An investigation is underway after 4 people died when 2 aircraft collided mid-air near Grasmere in Gauteng, on Monday night. The South African Civil Aviation Authority says its members were still on the scene yesterday afternoon, to collect evidence.

An investigation is underway after 4 people died when 2 aircraft collided mid-air near Grasmere in Gauteng, on Monday night. The South African Civil Aviation Authority says its members were still on the scene yesterday afternoon, to collect evidence.