A man who believes his brother disappeared four decades ago while on a secret anti-Castro mission climbed a radio tower behind the Miami Herald building Thursday and demanded the U.S. government release information about his sibling.

The man, who identified himself as Robert Annable, left a written statement at the base of the tower pleading with federal officials for any information about his brother Harrison, who disappeared from a fishing boat on Nov. 17, 1962, The Miami Herald reported on its Web site Thursday.

He spent four hours on the tower and hung an American flag upside down before climbing down to where authorities were waiting to lead him away.

In the note, he had threatened to burn the American flag by 5 p.m. if the government did not respond.

"I will hate to do this but I am fed up with the continuing secrecy and lies from the government and I hope to complete my promise to my father on his deathbed that I would find the truth of Harrison's disappearance," he wrote.

"This is not meant to be an affront to the brave Americans that have served and died for their country," he added. "It is to identify one who did the same, yet the country he loved denied, defamed, and likely destroyed him."

Annable's brother and two other men disappeared shortly after leaving Miami on what was supposed to be a lobster fishing expedition in the Bahamas, but Annable alleges that his brother's disappearance was connected to the United States' anti-Castro policies. Their boat, Revenge, was discovered days later, but their bodies were never found, the Herald reported.

Newspaper stories at the time showed U.S. authorities suggested Cuban government boats may have attacked or captured the men.

The disappearance was about a year and a half after the ill-fated Bay of Pigs invasion, in which Cuban exiles backed by the CIA tried to overthrow Fidel Castro's fledgling communist government.

U.S. Coast Guard Spokesman James Judge said Annable first contacted the Coast Guard in 1999 about his brother's disappearance. Judge said officials told Annable they had no information because their records are destroyed after 10 years.

Annable said he spent years seeking information from the State Department, CIA and other federal agencies to no avail. Shortly after President Bush was elected, the CIA closed the family's efforts to request information, citing national security concerns, Annable said in the statement.

"This is simply an act of civil disobedience in the hopes that my government, the media, or the people of Miami will help me learn the truth of what happened to Harrison," he said.