New Mexico ? A scientist and his wife who both once worked at Los Alamos National Laboratory were arrested Friday after an FBI sting operation and charged with offering to help develop a nuclear weapon for Venezuela.

They were accused of dealing with an FBI undercover agent posing as a Venezuelan agent, but the government did not allege that Venezuela or anyone working for it sought U.S. secrets.

Pedro Leonardo Mascheroni, 75, and Marjorie Roxby Mascheroni, 67, a U.S. citizen, were arrested Friday, a day after they were indicted. They appeared in federal court in Albuquerque, where Mascheroni, a naturalized U.S. citizen from Argentina, was ordered held pending another hearing Monday morning. His wife was released under strict conditions.

Kenneth Gonzales, U.S. attorney for New Mexico, said the indictment does not allege the government of Venezuela or anyone acting on its behalf sought or was passed any classified information.