A US scientist was arrested on Monday and charged with attempted espionage after trying to sell secret documents to an undercover agent he believed was an Israeli spy, the US Justice Department said.
Stewart David Nozette, who has worked for the US departments of defence and energy and NASA, was charged later in the day in a district court in Washington.
The 52-year-old from Maryland will appear in the court Tuesday and could face life in prison if found guilty.
"Those who would put our nation's defence secrets up for sale can expect to be vigorously prosecuted," said Channing Phillips, acting US attorney for the District of Columbia.
According to the affidavit, Nozette was contacted last month by an undercover federal agent who pretended to be from the Israeli intelligence agency Mossad.
Nozette agreed to sell classified information about US satellite systems in exchange for money. A few weeks later he dropped the information into a post office box that was set up by the undercover officer.