American Is Captured After Plane Is Downed in Nicaragua Territory

WASHINGTON, Oct. 7 - An American-built cargo plane that was shot down over southern Nicaragua on Sunday was operated by a private group led by a retired United States Army major general Reagan Administration officials said today.The officials said the plane was operated by an organization headed by the retired general, John K. Singlaub, and had taken off from El Salvador. It had flown down the Pacific coast of Nicaragua and turned inland to deliver ammunition and supplies to rebels seeking to open a southern front against the Sandinista Government in Managua.Spokesmen for the Administration, the State Department, the Central Intelligence Agency and the Department of Defense all emphatically denied that the flight was in any way connected with the United States Government

C.I.A. Denies a Role-Aides Point to PrivateRightist Organization

WASHINGTON, Oct. 8 - President Reagan strongly suggested today that he approved of efforts by private American citizens to help Nicaraguan insurgents fighting the Sandinista Government, including those Americans who sent in a cargo plane that was shot down on Sunday.But Administration officials disclosed that the Federal Bureau of Investigation had opened what was described as a "preliminary investigation" of those private activities as possible violation of American neutrality laws.Even so, President Reagan compared the efforts of private citizens at this time to those of Americans who joined the Abraham Lincoln Brigade in the 1930's to fight alongside Spanish Republican soldiers against Franco and his rightist Insurgents.