(CNN) -- A U.S. team led by envoy Robert King left North Korea on Saturday after winning the release of an American citizen who had been detained there, state media reported.
The KCNA report did not say whether the team left with Eddie Yong Su Jun.
Jun, a Korean-American businessman, was detained for "committing a crime" against North Korea after entering the country, KCNA had reported.
Jun admitted his crime during an investigation, the North Korean news agency said, but it did not specify what crime he had allegedly committed.
His release follows a visit by King, the special envoy for North Korean human rights, and Jon Brause, from the U.S. Agency for International Development. The group went there to assess food shortages that have left thousands starving after floods and harsh weather devastated North Korea's crops.
King and Brause "expressed regret at the incident on behalf of the U.S. government and assured that it would make all its efforts to prevent the recurrence of similar incident," KCNA said.
The news agency also said former President Jimmy Carter asked North Korea to pardon Jun.
"Taking all this into account, the ... government decided to set him free from the humanitarian" standpoint, KCNA said.
"We welcome North Korea's decision to release Eddie Jun," said State Department spokesman Mark Toner. He added that King was able to visit Jun on Thursday, and that it was the Swedish Embassy, which represents U.S. interests in North Korea, that confirmed the impending release to the American government Friday.
In King's discussions with his North Korean interlocutors, Toner said, King conveyed deep concern over the welfare of an American citizen in their custody, but said the purpose of King's visit was not related to the release of Jun.
"It's important to note and to clearly state that any decisions about food aid are not related in any way to any policy decisions if you will. It's a separate process all together," Toner said Friday.
The assessment team traveling with King will continue its work on the ground and "when they come back, we will look at their assessments, study it and compare to other assessments by other NGOs," and groups that have made similar trips, to make a decision on the amount of aid to extend, Toner said.
Though he could not reveal a total readout of Jun's current physical condition due to privacy concerns, Toner said it was his understanding that Jun was in "decent" health. The Swedish government had ongoing access to Jun during his detention, Toner said.
It was not known exactly when Jun would leave North Korea, but Toner said he would not be traveling with King.
While the United States praised the North for its action, the two countries are still a long way from normalizing relations.
"There are a number of things we would like to see North Korea do in improving relations with South Korea first and foremost before we see other steps on other issues," Toner said.
Tensions between North Korea and the West have spiked in recent years due in part to concerns over Pyongyang's nuclear development program.
The United States and South Korea held joint military drills in February, despite North Korea's warning to the South not to carry them out -- calling the exercises a provocation.
South Korea accuses the North of torpedoing and sinking one of its warships in March 2010, killing 46 sailors.
In November, North Korea shelled Yeonpyeong Island, killing two South Korean marines and two civilians. That same month, it detained Jun.
Two State Department officials, speaking on condition of anonymity because they were not authorized to release details, told CNN in April that Jun was a Korean-American businessman who had a visa to enter North Korea.
The U.S. suspended aid two years ago to North Korea because it suspected the donated food was being diverted to the military or not reaching those most in need.
North Korea has detained several Americans in recent years, increasing tension levels in what is already a rocky relationship between Pyongyang and Washington.
In 2010, Carter helped secure the release of Aijalon Mahli Gomes, a U.S. citizen who was fined about $600,000 and sentenced to eight years of hard labor for crossing over the Chinese border into North Korea. Gomes, who attempted suicide while in North Korean custody, was thought to be a Christian activist.
Two American journalists, Laura Ling and Euna Lee, were arrested after entering North Korea in 2009. They were sentenced to 12 years hard labor before being released in August 2009 after an intervention by former President Bill Clinton.