Kim Jong Ryul is a slightly built and lively 75-year-old with large glasses and a gray suit that seems several sizes too big. But Kim wears it anyway. It is virtually his only connection to his past.

“This is the suit I had on,” the North Korean native explains, “when I escaped.”

About 15 years ago, Kim says, he exchanged his upper-echelon North Korean government job for a lonely underground existence in Austria, where he remains in constant fear of assassination.

Kim is one of thousands who in recent years have run from the North Korean government’s grip. But his personal history, the subject of a new book, offers a rare taste of a higher-level North Korean’s contempt for his country’s totalitarian rulers, an anger that gave him the will to turn his back on his life and his loved ones.

For 20 years, the mechanical engineer and onetime army colonel who went to college in the former East Germany purchased industrial goods, luxury Mercedes-Benz cars and weapons for the North Korean leadership.

His shopping list also included such sensitive items as mass spectrometers that can be used, among other purposes, in identifying uranium and plutonium particles. Kim spoke fluent German, English and Japanese, having learned the latter, he says, from watching TV. Young, intelligent and well educated, he was the perfect person to send on lavish shopping sprees to Europe. Vienna was the ideal hub for business dealings in Germany, Switzerland and France, he says.

Through intermediary companies, he even bought goods from the United States, including the spectrometers, which are on the Nuclear Suppliers Group’s list of restricted, dual-use equipment, and pistols that North Korean leaders ardently collected.

“They all knew this was for North Korea,” he says, speaking of the middlemen he worked with. But his offers were difficult to resist, he says, because he paid in cash, 30% over the usual asking price.

At the same time, he says, he was secretly making a Western-style profit for himself. Without the knowledge of his comrades, he generally kept about 3% of the money from each deal, setting up a secret account in the Austrian private bank Schoellerbank, where he eventually amassed about $300,000.

In October 1994, Kim says, he fled to Austria, faking his death and going into hiding. “I lived for 15 years like a mole.”

Finally, he had enough and decided to tell his story to two Austrian journalists. The book spotlights his escape and his descriptions of the decadence and arrogance of North Korea’s leaders, who spared no expense to obtain whatever they craved while their own people were starving to death.

“After I turned 70 years old, I thought, I may die soon, and that is why I wanted to do this book,” Kim says during an interview in the office of his publisher in Vienna.

Kim says he sees no hope for political change in his homeland or of ever again seeing his wife, now 70, his 45-year-old son and his 39-year-old daughter. “I abandoned my family 17 years ago.”

The public stance that Kim is now taking differs from that of many North Korean defectors, who use pseudonyms or demand anonymity when they speak about their homeland or their life afterward.

In his years of freedom in Austria, Kim says, he has lived a lonely existence in a small village outside Vienna. He has maintained a low profile, paid all bills on time and otherwise steered clear of trouble so as not to attract attention.

“I have no friends,” he says.

“My principle was not to make many friends because I could start talking, then I might tell them something about myself and this would not be good.”

First he insists that his neighbors know his true story, but later says that they don’t.

“Nobody asks. They only greet and want to know what I will cook today,” Kim says, laughing.

“This book will be the death of me,” he says, but it seems that this thought doesn’t scare him much. Kim is fully aware that by speaking up he has also endangered his family in North Korea, with whom he has had no contact since he left Pyongyang in 1993.

“They will not kill my family, but will kick them out of the capital.” He says he is sorry for this but his need to tell his story to the world is more important.

“With this book I wanted to shout out loud for a last time, and then die. I want to expose these two Kims, the two dictators [the late Kim Il Sung and his son Kim Jong Il], to criticize them and to say that they are [terrible people] and their policy is filthy,” Kim says.

And still, the tiny but tough man does not sound as though he is going to give up on life just yet.

“Tomorrow or after tomorrow I will go into hiding again.” He smiles and assures a listener that he can easily disappear because he knows Austria so well. Or maybe he will go abroad.

First, however, he will have to see the Austrian police about all the illegal dealings he was involved in during his two decades in the service of the North Korean government.

His next appointment is to officially apply for asylum because Kim Jong Ryul is no incognito refugee in Austria anymore.

Damianova is a special correspondent.

Ju-min Park of The Times’ Seoul Bureau contributed to this report.