Several tribal workers were reportedly trapped when earth caved in while digging for semi-precious stones near Sajjanapalle hamlet G.K. Veedhi mandal in the district late on Tuesday evening.
Reports reaching here said of an estimated 15 tribal people, who went in search of gem stones, two sustained injuries in the accident.
The condition of others was not known as search and rescue operation could not be taken up after sunset due to hilly terrains in the remote area.
Accidents in the Agency belt have been occurring regularly due to unscientific mining.
Though there was lull in mining for a long time, it picked up during past couple of months.