L. Bruce Laingen, the highest-ranking American official held in Iran during the 444-day-long hostage ordeal that began there in November 1979, died on Monday in Bethesda, Md. He was 96.

His son Chip told The Associated Press that the cause was complications of Parkinson’s disease.

Mr. Laingen, a career diplomat, had been in Iran less than five months when militant students stormed the United States Embassy in Tehran, taking more than 60 hostages, mostly diplomats and staff members. Mr. Laingen was not there at the time, but he too was detained, at the Foreign Ministry elsewhere in the city.

A few hostages were soon released. But most, including Mr. Laingen, were held for more than a year before being released on Jan. 20, 1981, the day Ronald Reagan was inaugurated as president of the United States. It was a period of high drama and high tension that included a failed rescue attempt that left eight American servicemen dead.

Mr. Laingen heard that the embassy was under siege just as he was leaving a meeting at the Foreign Ministry.