The US envoy to the United Nations said Sunday that the Obama administration hopes two American journalists detained in North Korea will be released swiftly and safely. Still, Ambassador Susan Rice acknowledged there are no guarantees. Rice said the United States is continuing to work with Swedish diplomats who represent US interests in North Korea to win freedom for Euna Lee and Laura Ling. The journalists work for former Vice President Al Gore's San Francisco-based Current TV media venture. Rice said the two are safe, "to the best of our knowledge." Lee and Ling were detained by North Korean border guards March 17 while on a reporting trip to China. North Korea's official news agency has said they can be tried for illegal entry and "hostile acts." Rice spoke on ABC's "This Week."