Oil giant BP agreed to pay the largest criminal penalty in U.S. history for the 2010 oil spill in the Gulf of Mexico, a source close to the case confirmed Thursday to CBS News.

The person, who spoke on condition of anonymity because they were not authorized to speak on the record about the deal, also confirmed to CBS News that two BP employees face manslaughter charges over the death of 11 people in the explosion of the Deepwater Horizon oil rig that triggered the massive spill.

BP has booked provisions of $38.1 billion to cover its liabilities from the incident, but the company has said the final cost remained highly uncertain. BP also recently announced that it expects to make the final payment this year to a $20 billion trust fund to cover damage from the blowout.

In a pretrial court filing, the Justice Department said it would argue that BP’s actions and decisions leading up to the deadly blowout amounted to gross negligence.

“We do not use words like ‘gross negligence’ and ‘willful misconduct’ lightly,” a Justice Department attorney wrote. “But the fact remains that people died, many suffered injuries to their livelihood, and the Gulf’s complex ecosystem was harmed as a result of BP and Transocean’s bad acts or omissions.”

Click here for the full report by CBS News.