A jury in New Zealand convicted a woman on Tuesday of two counts of murder for killing her children, ages 6 and 8, hiding their bodies in suitcases and then fleeing to her native South Korea. Ms. Lee also admitted to wrapping the children in three layers of plastic bags then shoving them into suitcases, which she wrapped in more plastic bags and sealed with duct tape. But Ms. Lee, 45, had pleaded not guilty, citing mental illness. During the trial, her lawyer said that, after killing her children, Ms. Lee unsuccessfully tried to end her own life. She eventually fled to South Korea.