BEIJING - An American geologist held by Chinese state security agents who stubbed lit cigarettes on his arms was sentenced to eight years in prison Monday for gathering data on China's oil industry - a case that highlights the government's use of vague secrets laws to restrict business information.

In pronouncing Xue Feng guilty of spying and collecting state secrets, the Beijing No. 1 Intermediate People's Court said his actions "endangered our country's national security."

Its verdict said Xue received documents on geological conditions of onshore oil wells and a database that gave the coordinates of more than 30,000 oil and gas wells belonging to China National Petroleum Corporation and listed subsidiary PetroChina Ltd. That information, it said, was sold to IHS Energy, the U.S. consultancy Xue worked for and now known as IHS Inc.

The sentence of eight years is close to the recommended legal limit of 10 years for all but extremely serious violations. Though Xue, now 45 and known as a meticulous, driven researcher, showed no emotion when the court announced the verdict, it stunned his lawyer and his sister, his only family member allowed in the courtroom.

"I can't describe how I feel. It's definitely unacceptable," Xue's wife, Nan Kang, said by telephone, sobbing, from their home in a Houston, Texas, suburb where she lives with their two children.

U.S. Ambassador to China Jon Huntsman attended the hearing to display Washington's interest in the case. He left without commenting and the U.S. Embassy issued a statement calling for Xue's immediate release and deportation to the United States.

Xue's sentence punctuates a case that has dragged on for more than two-and-a-half years and is likely to alarm foreign businesses unsure when normal business activities elsewhere might conflict with China's vague state security laws.

Chinese officials have wide authority to classify information as state secrets. Draft regulations released by the government in April said business secrets of major state companies qualify as state secrets.

"This is a very harsh sentence," said John Kamm, an American human rights campaigner whom the State Department turned to for help last year to lobby for Xue's release. "It's a huge disappointment and will send very real shivers up the spines of businesses that do business in China."

Agents from China's internal security agency detained Xue in November 2007. During the early days of his detention they stubbed lit cigarettes into his arms and hit him on the head with an ashtray. His case first became public when The Associated Press reported on it last November.

Like IHS, many multinationals have come to rely on people like Xue to run their China operations. Another China-born foreign national, Australian Stern Hu who worked for the global mining firm Rio Tinto, was sentenced in March to 10 years for bribery and infringing trade secrets that dealt with iron ore sales to Chinese companies.

Born in China, Xue earned a doctorate at the University of Chicago and became a U.S. citizen, returning to his native country to work. By all accounts, including witness statements cited in the court verdict, Xue poured his energies into his work for IHS, trying to gather information on China's oil industry, contacting former school mates from his university days in China.

Two of the three other defendants sentenced along with Xue on Monday were school mates. Chen Mengjin and Li Dongxu, who worked for research institutes affiliated with PetroChina were each given two-and-a-half-year sentences and fined 50,000 yuan ($7,500). The other defendant, Li Yongbo, a manager at Beijing Licheng Zhongyou Oil Technology Development Co., was sentenced to eight years and fined 200,000 yuan ($30,000). Xue was also fined 200,000 yuan.

Li and Xue arranged the sale of the database - which was originally prepared by a Chinese company for sale to PetroChina's parent company and contained details on the coordinates and volume of reserves for the 30,000 wells - to IHS for $228,500, the court's sentencing document said.

A spokesman for IHS, which is based in Englewood, Colorado, said the company is disapp