The families of victims in two Boeing 737 Max plane crashes have asked for prosecutions and a fine of $24.8bn for “the deadliest corporate crime in US history”.

The families’ lawyer Paul Cassell said the amount was “justified and clearly appropriate” given “enormous human costs of Boeing’s crimes”.

In a 32-page letter seen by the BBC, Mr Cassell said that the US government should prosecute those leading the company when 346 people were killed in two crashes in 2018 and 2019.

The letter cited the apology by Boeing’s chief executive Dave Calhoun on Tuesday while he gave evidence to Congress.

“I apologise for the grief that we have caused,” he said, as he was heckled by family members of victims of the crashes.