STORY: Families of the 346 people killed in two Boeing 737 MAX crashes are demanding that the jet maker face a fine of close to $25 billion.

They put the request to the U.S. Justice Department on Wednesday.

A lawyer for the families said the amount was justified, saying Boeing was guilty of the "deadliest corporate crime in U.S. history".

Earlier in the week, the families had gathered at Congress as company chief Dave Calhoun was grilled over the incidents.

They weren't mollified by his show of contrition:

"I would like to apologize on behalf of all of our Boeing associates spread throughout the world, past and present for your losses."

Calhoun said Boeing took responsibility for the crashes, which were traced to a design flaw.

But the families say the aerospace giant neglected known safety issues, and must face prosecution.

"Strengthening the safety of the flying public is important, but there needs to be criminal charges for the people at the top, the people in the driver's seat who were responsible for 346 deaths, including that of my sister and every single face that you see here.''

After the crashes in 2018 and 2019, Boeing agreed to a deferred prosecution deal with the DOJ, shielding it from criminal charges - if it promised to improve its compliance program.

However, the department last month concluded that the firm had not honored all terms of the deal - something Boeing denies.

Prosecutors now have until early July to decide whether to press ahead with a criminal case.

They could also negotiate a plea deal with Boeing, or extend the deferred prosecution agreement.