BuzzFeed editor and Rolling Stone investigative journalist Michael Hastings died last week in Los Angeles in a fiery car crash. But there is growing speculation about whether his death was really just a tragic accident.

Hastings, 33, was best known for his 2010 Rolling Stone report on the Afghan war that ended up bringing down Gen. Stanley McChrystal. Close friends and associates, including Sgt. Joe Biggs, said Hastings sent out a chilling email shortly before his death, saying he believed the feds were investigating him and that he was onto a big story.

Biggs joined Megyn Kelly today on America Live, saying the email was "very panicked... and something didn't feel right." The LAPD has said that Hastings was driving his Mercedes at a high rate of speed and crashed, with the car bursting into flames, and that foul play is not suspected. Biggs said he finds the cops' version of events very hard to believe.

"His friends and family who know him, everyone says he drives like a grandma. So that right there doesn't seem like something that he would be doing. He had a lot of friends and family that cared about him. He had a good life to live. There's no way he would be acting erratic like that and acting that out of control," said Biggs.

Biggs said Hastings' email followed closely by the mysterious single-car crash "is just not a coincidence." He said "real questions" need to be asked, such as why the Mercedes exploded like it did and why the engine flew out of the vehicle.

He said Hastings was working on an unknown story involving the CIA and told people it would be the "biggest yet."

Watch the full interview!