Five members of a family accused of scheming to send sensitive information about Navy warships to China were indicted Wednesday on new conspiracy charges, prosecutors said.

The indictment, handed down by a federal grand jury, added counts of conspiracy to export U.S. defense articles to China, possession of property in aid of a foreign government and making false statements to federal investigators to existing charges.

Named in the supplemental indictment were Chi Mak, a U.S. citizen who worked for Anaheim defense contractor Power Paragon; his wife, Rebecca Laiwah Chiu; his brother, Tai Mak; Tai Mak's wife, Fuk Heung Li; and their son, Billy Yui Mak.

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Li, 49, and her 26-year-old son were already facing charges of making false statements and acting as agents of a foreign government, namely China, without prior notification to the U.S. attorney general.

Chi Mak, 66, Tai Wang Mak, 57, and Rebecca Laiwah Chiu, 62, were previously charged with one count of failing to register as a foreign agent.

The government claims that Chi Mak passed information about U.S. naval technology from his employer to his brother and that his nephew, Billy Mak, then helped encrypt the files onto CD-ROM computer disk. That disk was found hidden in the luggage of Tai Mak and his wife after they were arrested in October 2005 at Los Angeles International Airport as they prepared to travel to Hong Kong and Guangzhou, China, authorities said.

The new indictment includes three counts of actual and attempted unlawful export of defense articles for Chi Mak; one count of possession of property in aid of a foreign government for Tai Mak; one count each against Chi Mak, Tai Mak and Rebecca Chiu for making false statements; and one count against all five family members for conspiracy to export defense articles.

Ronald Kaye, an attorney for Chi Mak, said he hadn't seen the indictment. He said his client worked with sensitive information as part of his job, but never misused it or stole intelligence.

"My client is involved in an area of technology that is not classified — is not even prohibited from distribution," Kaye said. "It's a strong sign that they are desperately trying to find whatever counts can stick. They've overcharged this case consistently."

Stanley Greenberg, Rebecca Chiu's attorney, said his client was innocent.

"The evidence will eventually show she's not guilty, because it all grows out of the same facts," he said.

John Early, an attorney for Tai Mak, said he had not seen the indictment and couldn't comment.

Attorneys for the other defendants didn't immediately return calls left after business hours Wednesday.

According to the FBI, Chi Mak told investigators his brother was giving the information to a researcher at a Chinese university center that conducts operations research for, and receives funding from, the People's Liberation Army.

Prosecutors have said previously that authorities recovered from the disk restricted documents on the DDX Destroyer, an advanced technology warship. They also allege that they found two tasking lists in Chinese asking Mak to get documents about weapons and defense technologies.

The FBI originally arrested Chi Mak and his wife for investigation of conspiracy to steal U.S. government documents, although they were never charged with the offense. None of the defendants has been charged with espionage.

Chi Mak is in custody pending a March 20 trial. The other four are scheduled for trial on May 15. Tai Mak and Billy Mak are in custody; Fuk Li and Rebecca Chiu are free on bail.

A hearing on several defense motions is scheduled for Nov. 17.

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