Demonstrators light candles at a sit-in protest in Istanbul, Turkey, for 301 coalminers who died this month at the Soma Coal Mining Company, mainly from carbon monoxide gas, which spread quickly through the mine after an explosion. Five company officials have been arrested on negligence charges and Turkish prosecutors have confiscated company records indicating that management was aware of high levels of the toxic gas in the mine for several days before the explosion. South Africa’s own worst coal-mine disaster took place in 1960 at Coalbrook, an underground mine near Sasolburg, in the Free State, where 437 miners died, resulting in serious attention being given to closing a number of rock-engineering knowledge gaps, primarily in the area of mine pillar strength.