BEIJING (AP) _ A trading company executive and countless others snared in a multibillion-dollar smuggling and payoff scandal went on trial amid deep secrecy Wednesday in China's biggest corruption case in 51 years of communist rule.

Court officials said hearings began in five cities in the southeastern province of Fujian. But they had little other information. They said most court staff were banned from the courtrooms, and judges and prosecutors kept tight control on the proceedings.

It ``seems very mysterious,'' said a duty officer at the Intermediate People's Court in Zhangzhou who declined to give her name.

Among the unspecified number of defendants were the general manager of the Fujian-based Orient Group, Cao Xinghai, put on trial in Putian, and two other defendants in Zhangzhou, court officials in the two cities said. They refused to specify the charges against Cao or the other two, identified as Liu Fenghe and Li Lanying.

The secrecy illustrates the scandal's troubling scope for China's leaders. President Jiang Zemin, who heads the 61 million-member Communist Party, has declared clean government a goal of his rule. But the Fujian scandal has tainted members of the elite ruling circle, among them one of Jiang's proteges.

The government has used occasional prosecutions of high-level officials to show the party's determination to end rampant corruption that has eroded support for communist rule.

State-run newspapers carried reports Wednesday about a death sentence given to the deputy head of transport for Sichuan province for taking bribes and amassing wealth beyond his means. The court sentenced Zheng Daofang's wife and son to 15 and 12 years in prison, respectively, and seized property worth $209,000.

By contrast, no mention was made of the Fujian trials.

At the center of the trial is the bustling port of Xiamen, opposite Taiwan, and the Yuanhua Group. The company smuggled oil, cars and cigarettes through Xiamen and other ports and spent lavishly to buy official protection or silence.

As part of the operation, Cao Xinghai of the Xiamen-based Orient Group and the 11 other defendants provided Yuanhua with certificates, seals and other ``conveniences,'' allowing it to engage illegally in import-export trade, the Hong Kong Commercial Daily reported.

For their help, Cao and the others received $2.4 million annually in rents and payoffs, the Hong Kong newspaper said.

Officials have called Yuanhua's web of smuggling and payoffs China's biggest corruption scandal, although they put no amount on the value of goods and money that illegally changed hands. Hong Kong media have said the smuggled goods were worth $9.5 billion.

Among those arrested in the investigation were the national police force's immigration chief, the provincial deputy police chief, two deputy Xiamen party secretaries, a vice mayor, the city's customs head and the official in charge of Xiamen's undercover police.

Because of the number of defendants, the cases are being heard in courts in Xiamen, Fuzhou, Quanzhou, Putian and Zhangzhou.