Henry Raymont, an American journalist who was the first to report in 1961 that a U.S.-supported invasion of Cuba was underway at the Bay of Pigs, only to be immediately imprisoned by Fidel Castro’s forces and threatened with execution, died on Tuesday in Tepoztlán, Mexico, where he had long lived. He was 98.

His daughter, Sarah Raymont, said he died in his sleep at an assisted living home.

Mr. Raymont was a United Press International reporter on assignment in Havana when Cuban exiles came ashore in April 1961 at Bahía de Cochinos, the Bay of Pigs, on the island’s southwestern coast.

Theirs was a covert military operation intended to overthrow the Castro government, in power then for a little more than two years. The mission, financed and guided by the United States, was a thorough failure, and “Bay of Pigs” became a metaphor for almost any venture doomed because of inept planning.

“I gave the first news of the Bay of Pigs,” Mr. Raymont said years later.

Within minutes of his alerting his editors in New York, armed militiamen burst into his Havana apartment and hauled him off to military intelligence headquarters. He was accused of being an enemy agent and told he faced the death penalty. Dozens of others were also detained. Some, Mr. Raymont said, were executed.

“I was going to be shot,” he said. But diplomatic efforts on his behalf led to his being freed after six days.