ROCKVILLE, Md. (AP) -- A prosecutor says a wealthy stock trader sacrificed safety for secrecy before a fire killed a man who was helping him dig a network of tunnels for a nuclear bunker beneath his Maryland home.

But a defense attorney for 27-year-old Daniel Beckwitt told jurors Wednesday that the deadly fire that killed Beckwitt's friend was an accident, not a crime.

The jury heard opening statements for Beckwitt's trial on charges of second-degree murder and involuntary manslaughter in the September 2017 death of 21-year-old Askia Khafra.

Montgomery County prosecutor Marybeth Ayres said Beckwitt created a "death trap" in his home, with mounds of trash blocking his escape.

Defense lawyer Robert Bonsib said Khafra was a willing participant in the project, even though he worked in the tunnels for days at time.

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