The tragedy happened just outside of Kinshasa, Africa’s most populated city. Twenty-six people died, and all but two of the victims were women, authorities said. Two others were seriously injured. The incident was not unusual in the Congolese capital, which is plagued by outdated infrastructure and home to sprawling makeshift neighborhoods that are not zoned for housing. Architects said the accident could have been avoided by regulating planning under high-voltage electricity lines.