Their arrest complicates Washington’s already thorny relations with the North, including an increase in tensions over North Korea’s plan to launch a satellite between April 4 and April 8. American officials say they believe that the rocket launching is a cover for testing ballistic missile technology.  Also Saturday, the North told international aviation authorities that it would close two international air routes through its airspace from April 4 to April 8 for the satellite launching, according to the Japanese and South Korean governments.  It remains unclear under what circumstances Ms. Ling and Ms. Lee were detained. The Chosun Ilbo, South Korea’s leading newspaper, reported Saturday that the American television crew appeared to have crossed the river border — either intentionally or not — while trying to get a closer shot of North Korea.  Citing Chinese sources on the border, the newspaper reported that the three American journalists and their Chinese guide, an ethnic Korean, crossed the border around sunrise on Tuesday near Tumen, a Chinese border city.  The Tumen River, which forms the border, is only 20 or 30 yards wide in the area, according to human rights advocates who have visited there. Much of the river bed is dry, and the shallow water is frozen at this time of the year. It is difficult to tell where the border lies, and North Korean guards often stay hidden in bunkerlike guard posts, they said.  The two men in the group, Mr. Koss and the guide, who was not identified, freed themselves from the armed North Korean soldiers and ran back to China, while the two women were overpowered, The Chosun Ilbo reported.  Current TV, based in San Francisco, was founded by former Vice President Al Gore.  A version of this article appears in print on , on Page A13 of the New York edition with the headline: North Korea Says It Is Holding Two American TV Reporters. Order Reprints| Today's Paper|Subscribe
North Korea confirmed that it had detained two American journalists on charges of “illegally intruding” into the Communist state through its border with China.