TRW Inc. has agreed to plead guilty to three charges of conspiracy and will pay $6 million in criminal penalties and restitution, the U.S. attorney's office said Thursday. The conspiracy charges stem from the company's attempt to defraud the government by inflating labor costs on Defense Department contracts, including costs for work done on jet engines and the M-1 Tank. Besides a $3 million fine and penalty, TRW will pay an additional $3 million in restitution on a pending civil case in the matter. That case was filed by former TRW employees who were fired for allegedly engaging in price-hiking schemes. The U.S. attorney's office said the fines and penalties against the suburban Cleveland company are the largest ever assessed against a defense contractor for procurement fraud.