Barnaby Jack, a hacker who claimed he could stop a man's heart from 300 feet away by exploiting a flaw in medical implants, died Thursday in San Francisco at age 35.

Jack was found dead Thursday evening at an apartment in Nob Hill. The San Francisco medical examiner confirmed Jack's death but did not provide a cause as the investigation is still ongoing. Foul play has been ruled out.

Jack was well-respected among hacker circles and experts in the Information Security scene. Most famously, in 2010 he uncovered a way to make ATM machines spew out cash on command, a practice that became known as "Jackpotting." Two years ago, he developed a hack that could cause insulin pumps to deliver fatal doses. Jack was working for McAfee at the time, but his work prompted medical device maker Medtronic Inc. to completely rethink the way their designs. That work led to his latest discovery — an exploit in the wireless system that connects pacemakers and defibrillators to hospital monitors that he felt could have "lethal consequences."

Jack was scheduled to make an appearance at the annual Black Hat hacking conference to deliver his findings in presentation called "Implantable Medical Devices: Hacking Humans."

In a statement, Black Hat wrote: "We have lost a member of our family. Everyone would agree that the life and work of Barnaby Jack are legendary and irreplaceable."

Jack's most recent employer, security services firm IOActive also took to Twitter to express their sentiments: