N. Korea site 'apocalyptic'
The death toll the train blast continues to rise.
People across the border in China heard the explosion.
North Korea's rare call for help
(CNN) -- An international aid official has described the site of a massive train blast in North Korea as "apocalyptic" and says urgent medical help is needed.
Richard Ragan, director of the World Food Programme in North Korea, visited the blast site in Ryongchon near the Chinese border and said he was shocked at the widespread destruction.
Survivors were nursing horrific injuries and hospitals lacked medical resources to treat the injured, he said of the aftermath of Thursday's blast.
Neighboring China has sent truckloads of aid into Ryongchon including tents, food items and other relief materials.
On Monday, North Korea finally accepted a South Korean offer of humanitarian relief.
Pyongyang had balked at allowing South Korea transport aid supplies overland through the heavily guarded Demilitarized Zone that separates the North from the South.
But after some negotiations, Seoul agreed to ship $1 million worth of supplies to the North Korean port of Nampo on the western coast of the Korean Peninsula.
At least 161 people were killed in the explosion at Ryongchon Railway Station -- at least 76 of them were children, John Sparrow of the International Federation of the Red Cross said on Sunday quoting North Korean Red Cross officials.
Survivors, many suffering burns, are being treated in poor and overcrowded conditions in nearby North Korean hospitals.
"The tragedy was horrific, the center of Ryongchon was sort of apocalyptic looking with most of the buildings leveled," Ragan told CNN.
"The blast site itself in the center of Ryongchon looks like as much as two thirds of the city center has been destroyed."
Ragan visited a hospital in the nearby city of Sinuiju where over 360 survivors were being treated and said it was "one of the worst hospital scenes I have seen in my 20 years of doing humanitarian relief."
The hospital facilities were very rudimentary and doctors faced shortages of medical supplies, Ragan said.
Many of the injured -- including one woman with burns on 90 percent of her body -- would be difficult to treat under the best of circumstances.
Children were lying on cabinets because there were not enough beds.
He said North Korea needed medicine, food, building supplies and cooking stoves and other utensils.
Ragan said that aid was coming quickly, in part because of international efforts already in place in the impoverished country. He said he passed eight trucks carrying supplies from China.
On Saturday, North Korea broke its silence on the blast releasing a statement saying "carelessness" caused the explosion.
The country's state news agency reported that electrical contact detonated train cars loaded with a chemical component of fertilizer.
Swedish Ambassador Paul Beijer said the accident occurred at Ryongchon's rail yard while workers were moving two freight cars carrying explosives slated for canal construction and they came in contact with a live electrical wire.
Beijer also said that, "all indications are that it was simply an accident. A very bad one."
The blast happened nine hours after North Korean leader Kim Jong Il passed through the station, en route to Pyongyang after a recent visit to China, Yonhap reported.
The blast destroyed or damaged thousands of homes and other buildings. U.N. officials estimate about 40 percent of Ryongchon was destroyed.
CNN Beijing bureau chief Jaime FlorCruz in Dandong and correspondent Sohn Jie-ae in Seoul contributed to this report