Kemberg/Dessau-Roßlau (dpa/sa) - With the help of sonar technology, emergency services in Bergwitzsee near Kemberg (Wittenberg district) want to continue looking for a missing stand-up paddler. A police spokesman said on Monday. A large contingent of rescue workers had searched in vain for the man until Sunday evening. According to witnesses, the 47-year-old fell from his stand-up paddle board into the lake on Saturday afternoon and did not reappear. When using sonar technology, sound wave pulses can be used to search for missing persons in the water.