BP will plead guilty to manslaughter charges stemming from the 2010 Deepwater Horizon explosion and oil spill in the Gulf of Mexico, and agreed to pay $4.5 billion in government penalties, Attorney General Eric Holder announced Thursday.

Of the penalties, $4 billion will resolve criminal charges. An additional $525 million will be paid to resolve claims brought by the Securities and Exchange Commission that BP lied to investors by understating the amount of oil flowing into the Gulf.

Separate from the corporate manslaughter charges, a federal grand jury returned an indictment charging the two highest-ranking BP supervisors on board the Deepwater Horizon on the day of the explosion with 23 criminal counts. The two men were charged with seaman’s manslaughter and involuntary manslaughter for each of the 11 men killed in the blast, as well as a criminal violation of the clean water act.

The grand jury also charged BP’s second-highest ranking representative at the company’s unified command post with hiding information from Congress and allegedly lying to law enforcement officials.

The company also will plead guilty to a felony count of obstruction of Congress, a misdemeanor count under the Clean Water Act and a misdemeanor count under the Migratory Bird Treaty.

Holder said the dollar amount of the penalties and the criminal charges against both the company and individuals are unprecedented.