31.   The trouble is that such an arms operation could not have remained secret for long.

32.   They did and they kept their mission secret for many years.

33.   Typically, they keep their stories secret for a decade or more, Anderson says.

34.   Why did Venona stay so secret for so long?

35.   Operations were officially kept secret for security reasons.

36.   Or were the terrorists truly able to conduct a massive, highly coordinated operation and keep it almost perfectly secret for months, even years?

37.   Palestinian negotiator Saeb Erekat said the two sides had agreed to keep those ideas secret for now.

38.   Although the report was leaked to the media last month, portions were kept secret for reasons of state security.

39.   By The Associated Press The work of U.S. special operations forces during wartime can remain secret for years.

40.   Details of the offensive were being kept secret for operational reasons.