In tightly controlled North Korea, virtually no one speaks freely. That almost surely applies to captured American pilot Bobby Hall.

Hall's alleged "confession," released Thursday by the official North Korean news agency, is laced with strange language suggesting it was far from voluntary."Look at the wording," said Kim Chang-su of the independent Korea Institute for Defense Analyses. "It's full of terms like `grave infringement' and `grave challenge.' The North Koreans use this language all the time.

"I'm sorry, I don't believe this was the work of Mr. Hall," he said.

In the statement, Hall said that crossing into North Korea in his OH-58C helicopter was a "criminal action (that) is inexcusable and unpardonable." He said he was on a reconnaissance mission.

"I believe that such an intrusion is a grave challenge to the (North) Korean People's Army," he said.

Several times, Hall's alleged statement uses North Korean names and spellings of places - terms never used by the South Koreans and Americans, Kim said.

North Korea has said little about Hall since his helicopter went down and he was captured, and the statements it has made have sometimes been conflicting.

Hall signed the handwritten statement Sunday, according to the North's official Korean Central News Agency. But a North Korean official was quoted Tuesday as saying Hall was being "uncooperative," delaying its investigation.

The North released a photograph of the seven-page statement Thursday. There was no immediate comment from U.S. officials as to whether the handwriting appeared to be Hall's.

Kim said North Korea may be ready to free Hall, and chose to release the statement now to get maximum propaganda value.

In South Korea, where 37,000 U.S. troops are based, the American military runs regular announcements on its television station advising soldiers not to cooperate if captured.

"I'm sure Mr. Hall knows this code of conduct well," Kim said.