The parents of a 21-year-old U.S. Army private who apparently defected to North Korea have received the first communication from their son since his mysterious disappearance Aug. 28 across the two-mile-wide demilitarized zone separating the two Koreas.

Norval White, father of PFC Joseph T. White, called The Washington Post late Saturday to describe the contents of a letter, dated Oct. 27 but not received at the Whites' St. Louis home until Friday.

Although the letter provided the first evidence that the soldier was residing in North Korea, apparently of his own volition, little is known of his current whereabouts.

"The letter contained only assurances that he is well and an expression of love and concern for his family and friends," said White, who works at a General Motors truck assembly plant in St. Louis.

"He makes no comment or explanation of what happened on the DMZ. He says that he helped harvest some crops and that he teaches two university students English, and he wished he had a dictionary and an almanac."

The elder White said that even though the letter "is three or four months old, we're just grateful to God to have it. Until this, we didn't even know for sure Joey was alive.

The handwritten letter was datelined Pyongyang, capital of North Korea.

White quoted his son, the fourth of five children, as saying that "the people he had met were very moral, hard-working and have great respect for authority, teachers and senior citizens."

While White declined to read directly from the letter, he acknowledged that its tone seems to argue strongly that his son has no intention of coming home and that his defection was voluntary, as has long been claimed by Army officials.

"Yes, it does; yes, it certainly seems that way," White said quietly. "Christmas was very bad for us, but we feel a little better now.

"Maybe one day we'll know why he did it--not that it would make make any difference in his current situation. You've got to go with the present situation, and that seems to be that Joe went over there on his own."

The letter came to White and his wife Kathleen through the U.S. Postal Service from the office of Sen. John C. Danforth (R-Mo.), where it was received earlier last week from North Korea's permanent observer mission to the United Nations.

It is not known how the letter arrived in the United States or why it took so long to arrive.

A spokesman at the North Korean mission in New York said yesterday that the letter had arrived by diplomatic pouch but refused to elaborate.

Danforth and Rep. Richard A. Gephardt (D-Mo.) have been working on the Whites' behalf to get some word of their son.

Life is eerie and almost surreal for U.S. servicemen along the bunkered no-man's land separating North and South Korea. Early on Aug. 28, White, a member of the 31st Battalion of the 2nd Infantry, was on police duty, monitoring the North Korean frontier 15 yards away.

Before sunrise, according to Army investigators, he walked calmly to the chain-link fence surrounding a guard post, apparently used his M16 rifle to shoot the lock off the gate, and fled north. At 7:20 a.m., a U.S. soldier saw White, carrying his rifle, on the other side of the border.

North Korea's news agency later quoted White as saying he had willingly defected.

For weeks, his parents continued to believe their son had not defected. Mrs. White had stood in front of their home in a working-class, south St. Louis neighborhood and told reporters the story made no sense.

"He would have had to change his whole personality in a week," she had said in telephone interview. The only way she might maintain interior peace in the future, she said, is by promising herself that she will find enough money and obtain permission to visit her son in North Korea and ask why he left.

"We're going to try to send him that dictionary and almanac," Norval White said on Saturday. " . . . We'll get them and just send them to Joe White, care of Pyongyang, North Korea. That's all we have.

"Many wonderful, supportive people prayed that we might receive some contact, and we want to thank them all and say that in turn we ask God to bless each and every one of them," White said. "We've had letters from all over the country."