It's not like openly confirmed, but he died in a solo traffic accident where his car rapidly accelerated into a tree.
The surface story is that he was doing meth or something, but 2013 is around the time that they started being able to digitally control accelerators through wireless connections, so it's not impossible that he was just one of the first they tested it on.
His reporting was highly critical of the Alphabet agencies and the surveillance state. Even got a general to step down after his reporting, so he was definitely not liked by the apparatus.
i looked it up because i was curious and the first article was a Politico article smearing the Huffington Post for even suggesting it (despite Politico not having any counter evidence) so I'm immediately convinced its real 👁️