KARACHI (AFP) - Officials were forced Thursday to repair a leak in its oldest nuclear power plant, lying on the outskirts of its economic hub Karachi on the Arabian Sea coast, an official said. An emergency had been declared yesterday after leakage of heavy water was reported, a Karachi Nuclear Power Plant (KANUPP) official told AFP. KANUPP is the oldest nuclear power plant in the country. It is owned and operated by state-run Pakistan Atomic Energy Commission and has been in commercial operation since 1972. Our staff controlled the situation after a few hours and the emergency is over, the official told AFP. During the emergency no radioactivity was recorded. None of our staff is affected, said the official. He said the plant had been closed for routine maintenance since October 5.