A retired U.S. government official was held secretly in a Nigerian prison for two weeks and was released only after a behind-the-scenes protest effort that reached to the White House.

Kenton L. Harris, 63, of 7504 Marbury Rd., Bethesda, was detained by Nigerian authorities on Feb. 16 and imprisoned on Feb. 22 without being charged or allowed to communicate with his family or U.S. embassy officials.

He was freed and allowed to return to the United States on March 7 after protracted maneuvering that involved the intercession of the State Department, the White House, Pennsylvania Gov. Milton J. Shapp and Sens. Hubert H. Humphrey (D-Minn.), Warren G. Magnuson (D-Wash.) and Jacob K. Javits (R-N.Y.).

During that time, details of the incident were kept secret by Harris' family and the officials involved. But in a recent interview, Harris gave this account of his ordeal:

He is an agricultural chemist who worked for various federal agencies for 34 years before retiring from the government in 1969. Earlier this year, he was hired as a U.S. government-paid consultant to visit several African countries and advise on grain-storage problems.

On Feb. 16, Harris and a traveling companion, Carl Lindblad, were on a Nigerian airliner bound for Cameroon, when Harris took some photographs of the countryside from the plane's window. "I had no idea, but that's apparently forbidden," he said. "At any rate, it got some of the passengers very agitated."

When the plane landed at the Nigerian town of Calabar, two passengers denounced Harris to Nigerian soldiers as "a CIA agent." Lindblad was allowed to continue on the flight, but Harris' passport was confiscated and he was forced to remain in Calabar for what stretched into six days of questioning by first army and then police officials.

On Feb. 22, he was put aboard a plane under armed guard, flown to the capital, Lagos, and put into a prison cell. "No one would tell me why I was being held or if I would be charged," he said. "They also ignored all my requests to contact our embassy or my family."

Initially, he recalled, "I was stripped to my jockey shorts and put in a cell that had four concrete walls and a dirty rubber mat on the floor. The only other thing it had was swarms of mosquitoes. I was eaten alive. By the next morning, I looked like I had chicken pox."

He later was switched to another cell and was allowed periodic exercise in the prison yard. "Except for verbal abuse, I wasn't really mistreated," Harris said."I was never beaten. I eventually managed to finagle myself a T-shirt to go with my shorts, and I was fed well, by Nigerian standards.

"But," he added, "it was a miserable, filthy place. The stench made you want to choke. The guards seemed arbitrary to the point where you didn't know what they would do. In my case, I was just forgotten -- no more questioning, nothing."

In the meantime, Lindblad had reported Harris' arrest to U.S. authorities, and officials of the embassy in Lagos began making inquiries. Twice they went to the prison, but were told both times by Nigerian police that Harris wasn't there.

State Department officials said the embassy in Lagos sought to talk with Harris under a consular agreement giving them access to U.S. citizens who are arrested in Nigeria. However, the officials added, the embassy was temporarily stymied by Nigerian assertions that Harris wasn't being held. "To this day, they haven't admitted that he was being held," one department source said.

A number of foreigners have been arrested in Nigeria in the year since the former head of state, Gen. Murtala Mohammed, was assassinated during a coup attempt. That, some State Department sources said, "has created a climate where it would have been counterproductive to charge in and demand his release. It would have created a risk of getting their backs up and making his situation worse."

In the United States, Harris' family contacted Shapp, a family friend. He talked with White House officials, who asked the State Department to increase its efforts. Other friends took the initiative in asking the three senators for help, and they also communicated their concern to State.

The department finally advised the Nigerian ambassador in Washington, Edward O. Sanu, of the growing concern here about Harris. Sanu, who was returning to Lagos for consultations, promised to pursue the matter with his government.

"I don't know exactly what happened," Harris said, "but I do know that within hours after the ambassador arrived in Lagos, I was freed. I had a brief rest at our embassy, and then I was on a flight to New York."

In retrospect, Harris said, he believes that "it was the high-level pressure from Washington that had the most effect on getting me out." He quickly added, though, "I'm not criticizing our State Department people, who were all very nice and who acted according to what they felt was my best interest."

He has a somewhat different attitude toward his former captors. Since returning to Washington, he has sent a letter to Sanu charging that "my family and I have been subjected to suffering caused by the wanton and deliberate misuse of power" and asking that "you apologize to me for these excesses."

A spokesman for the Nigerian embassy said the letter had not yet been received and that any comment would have to come from the ambassador, who is still out of the country.