Frederick P. Picard III, 49, a former Foreign Service officer and authority on African affairs, died Tuesday in Tehran, Iran, following surgery.

He was working for the General Telephone and Electronic Corp. as a special assistant in its Iran telephone development program. He had joined the corporation in 1975.

Mr. Picard joined the State Department in 1953. A native of Nebraska, he had graduated from the University of Nebraska and the Fletcher School of Law and Diplomacy of Tufts University.

He hold consular and diplomatic posts in Rhodesia, Iran, Zanzibar and Nigeria.

He made headline in 1964 while serving as consul in Zanzibar when he was arrested during an argument with President Abald Karuma, head of the country's new revolutionary regime, and marched away at gunpoint.

The act was seen as a comic opera facet of a sinister situation. Officials said then that never in recent memory had a chief of state arrested the chief of a diplomatic mission.

Mr. Picard was held overnight under house arrest, then permitted to depart by chartered plane the next day, and a crisis was averted.

During his Foreign Service career, he also had three tours of duty in the 1960s in Washington with the State Department's Bureau of African affairs. He resigned from the Foreign Service in 1970.

He then was executive director of the Carroll Center for the Blind in Newton, Mass., and director of development of the Massachusetts Eye and Ear Hospital in Boston until 1975.

He is survived by his wife, Helen, a daughter, Catherine, and a son, Fraser, all of Tehran: two other children, Allson, a student at Sarah Lawrence College, and Frederick, a student at Ohio Wesleyan University, his mother, Margaret Picard, of Lincoln, Web., and two sisters.