The miscreants gave the siblings a tremendous trashing and looted cash and valuables from the shop.
Later, the criminals set fire to the shop keeping the two brothers inside.
On information, other Bangladeshi expatriates rushed to the spot and rescued the two brothers with burn injuries.
They were taken to a local hospital where Ibrahim succumbed to his injuries at 7am on Saturday.
Ibrahim went to South Africa in 2011 aiming to make fortune and later opened a grocery shop in Pretoria, while Ismail had been there barely three weeks ago to work in his shop.