Singlaub has denied any connection to the downed plane, but has admitted links to the private aid network. Owen has steadfastly declined comment on the issue. One of his friends said Saturday that he had left Washington for a vacation in New England this weekend.

The chief link in the vice president's office to the private aid effort was Donald Gregg, Bush's national security adviser, the officials said.

The officials said that after the congressional aid ban, Gregg remained in contact with the program through Max Gomez and Ramon Medina, two Cuban-Americans.

According to Singlaub, who spoke at a news conference in Washington last week, Gomez was active in the CIA in the Bay of Pigs operation.

For the last 18 months, Gomez has worked as an adviser to the Salvadoran air force at the Ilopango air base near San Salvador. Hasenfus told his Sandinista captive that his doomed C-123 took off from Ilopango.

UNCLEAR AREA

It is still unclear, however, who ordered, controlled and paid for the mission of the downed C-123.

Despite the interconnections between the administration and the private network, officials insist that the government played no direct role.

"So far, " one official said Saturday, "the proof is the scandal in the press but there is no legal proof" of administration involvement.

That lack of proof has stymied past efforts to investigate the administration's role in supplying the contras.

On Aug. 12, Rep. Lee Hamilton, chairman of the House intelligence panel, wrote Rep. Ronald Coleman, D.-Texas, who had requested that the House order Reagan to turn over documents on North's contacts with the contras.

"As you are aware, there have been numerous stories published in the press during the last year alleging that members of the National Security Council violated the Boland amendment prohibiting certain assistance to the contras . . . , " the letter said. "Based on our discussions (with White House officials) and review of the evidence provided, it is my belief that the published press allegations cannot be proven."

An administration official said Saturday that he doubted that any hard evidence existed that the administration violated the ban against aiding the contras.

"One thing is to say they (administration officials) know, but it's quite another to be able to show actual proof that they had a hand in it, " the official said. "Without legal proof, there is no prosecution."