South African authorities said they were investigating how domestically produced electronic equipment ended up on Russian drones used in attacks on Ukraine. The laser rangefinder was made by Lightware Optoelectronics Ltd., a company based outside Pretoria. It can be used to measure distances and trigger detonations. It was unclear how Russia obtained the equipment, which is not intended for military use, Lightware said in response to questions this week. It blamed “unscrupulous” buyers. Under South African law, companies are prohibited from exporting weapons to a country in active conflict without permission from the government’s National Committee for the Control of Conventional Arms, or NCACC.