The leak of Democratic National Committee internal emails is reportedly a result of Russian hacking, and now the FBI has said that it is investigating the hack:
A statement from the FBI confirmed that it is "investigating a cyber intrusion involving the DNC," adding that "a compromise of this nature is something we take very seriously."
A more complicated, but equally important question to “who hacked DNC computers” is “are the results of that being used intentionally to help Donald Trump, and if so, is his support of Russian President Vladimir Putin’s priorities a factor?” But an FBI investigation into who got into the DNC computers to begin with is an important starting point.