Fong Fuming, of West Orange, N.J., was accused of obtaining secrets and giving bribes.
After a seven-hour trial, Beijing's No.1 Intermediate People's Court said an additional hearing would be held to consider new evidence and information raised at the proceedings, the U.S. Embassy in Beijing said.
No date was set, said the embassy, which sent a consular officer and a Chinese employee to the trial.
The delay was unusual for China, where trials often last just a few hours. The embassy had no other information, and officials at the court and at China's Foreign Ministry also said they had no information.
Fong's family had been hoping that President Bush's visit to Shanghai for a meeting of Pacific Rim leaders would help win his release. Mr. Bush held talks Friday with Chinese President Jiang Zemin in their first ever meeting.
Fong is accused of obtaining 43 secret government documents from a state power official and of distributing $245,000 in bribes. China's Foreign Ministry says he was indicted Sept. 14.
The U.S. State Department gave the date of Fong's indictment as Sept. 29. It has accused China of violating international standards by holding Fong for months without indicting him.
There also are differing accounts of how long he has been held.
A U.S. lawyer for his family said Fong was detained Feb. 28, 2000, when he was in China to help an American power firm bid for a contract. The lawyer, Jerome A. Cohen, said China violated its own laws by holding Fong for so long without indicting him.
But the Foreign Ministry said Fong was detained Aug. 28, 2000. It said Fong was dealt with according to law.
Fong's family kept silent for months about his detention, hoping to win his release. They went public in September, in part because of mounting concern over China's treatment of Fong, Cohen said.
The 66-year-old is hard of hearing and nearsighted, but officials took away his hearing aid and, most of the time, his glasses, too, Cohen said.
China's detentions of U.S. citizens and residents have added to tensions in its relations with Washington this year.
In July, an American business professor and two Chinese-born U.S. residents were convicted of spying. China, eager not to damage ties with its second-largest trade partner, released them ahead of a visit by U.S. Secretary of State Colin Powell.
Fong worked in China's power sector before moving to the United States. He became a U.S. citizen in 1994 and advised foreign firms about power projects in China and elsewhere in Asia, Cohen said. Fong's wife and two sons also are U.S. citizens.
Chinese authorities accused Fong of bribing bid officials to obtain technical documents, and said they might be secret, Cohen said. He said the documents were apparently about previous projcts similar to the one the American firm bid for and later won.
Fong says he did not know that the documents, which he stored on his computer, were secret, Cohen said.
Fong's American-educated father-in-law also was an engineer in China, but was arrested in 1958 on suspicion of spying for the United States. He died in prison in 1961. The government later admitted he was innocent, Cohen said.
By JOHN LEICESTER
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