The North Korean in charge of rescue efforts told the Chinese news agency Xinhua that 154 people are confirmed dead and 1,300 injured from the blast, which happened on 22 April in the town of Ryongchon.
Jang Song Gun said an oil tanker collided with wagons of ammonium nitrate fertilizer, knocking down an electricity pole, which triggered the blast.
"The health system is in a very poor state, they don't have any consumables, they don't have any medicines."
In a separate statement, the North Korean state news agency said today the damage was "very serious" and blamed the disaster on "carelessness."
No aid has yet reached the scene, but international relief teams have headed to the site, and offers of help have been coming in from around the world.
South Korean Unification Minister Jeong Se-hyun today announced immediate emergency aid of $1 million.
"The [South Korean] government will send emergency aid supplies and medicines worth $1 million through the Red Cross," he said.
China has also offered $1.2 million in emergency relief, and U.S. State Department spokesman Richard Boucher said yesterday that the United States is willing to help.
"We have provided assistance in the past for humanitarian needs in North Korea, and there's no particular obstacle to that. We'd have to look at what was needed and whether we could provide it."
In Beijing, a returning aid worker said the country is ill-equipped to handle a large-scale emergency. Anne O'Mahony of the Irish relief agency Concern was briefed on the accident by the North Korean government.
"The health system is in a very poor state, they don't have any consumables, they don't have any medicines, they don't have tablets. They have a lot of trained staff, but very little for them to work with," she said.
It's rare for the North to admit to such incidents as the disaster. The isolated country is also usually slow in seeking outside help.
But in today's statement it thanked the international community for its offers of help and messages of condolence. Another veteran aid worker said he thought the disaster could force the reclusive state to open up.
German doctor Norbert Vollertssen, who spent two years in North Korea, told Reuters he saw parallels with the way the Chornobyl nuclear disaster forced the Soviet Union to deal with the world more openly.