NEW YORK: Pakistan currently has between 25 and 50 nuclear weapons, mostly relatively simple uranium arms with "modest" yields around the size of the bombs that destroyed Hiroshima and Nagasaki, a journal claimed on Thursday. The Nature magazine's claim followed media reports that satellite photos of Pakistan's Khushab nuclear site have shown what appears to be a partially completed heavy-water reactor capable of a 20-fold increase from its current nuclear capabilities.