Three former executives at Berkshire Hathaway’s General Re insurance unit and a former American International Group Inc. executive have been indicted by a federal grand jury on charges of fraud and conspiracy, the Justice Department announced Thursday.

Those charged are Ronald Ferguson, who was General Re’s chief executive; Elizabeth Monrad, the former chief financial officer; Robert Graham, the company’s former assistant general counsel; and Christian Milton, who ran AIG’s reinsurance division.

Each defendant, if convicted on all 13 criminal counts of conspiracy, fraud and making false statements to the Securities and Exchange Commission, could face a maximum 95 years in prison and $7.75 million in fines.