Seven out of 10 North Koreans are believed to have insufficient food, a South Korean aid group said, citing the communist nation's distribution offices.
The Seoul-based Good Friends aid agency said there are concerns among midlevel North Korean officials that residents of cities who do not receive regular wages or rations and have no arable land could begin to starve, adding that farmers also have had food shortages since last month.
"Massive deaths caused by starvation do not occur, but malnutrition is worsening, resulting in some deaths," the group said in a regular newsletter.
It declined to give details of where it obtained the information. However, many of its previous reports of what was happening inside isolated North Korea have later been confirmed.
Food shortages were exacerbated by massive floods last summer and South Korea's suspension of food aid to protest North Korea's missile tests in July, according to the New York-based group Human Rights Watch.