On Saturday, it was reported that U.S. Supreme Court Justice Antonin Scalia has died at the age of 79. How did Scalia die? While details are still forthcoming, the longest-serving justice of the Supreme Court died of natural causes in his sleep in Texas, according to CNN. The San Antonio Express-News reported that Scalia was at the Cibolo Creek Ranch, a luxury resort 33 miles north of Marfa in West Texas. After attending a private party on Friday night, Scalia did not come down for breakfast Saturday morning. A government official told CNN that Scalia said he "wasn't feeling well" before going to bed on Friday night: Scalia was found unresponsive in his room when a member of the staff went to check on him Saturday morning.

The late justice would have turned 80 next month. It is currently unknown if Scalia suffered from any pre-existing medical conditions at the time of his death. Unlike the President of the United States — whose physical exams are made public — Supreme Court justices do not share that same health information. If anything, the health of sitting justices is kept as private as possible. Notable exceptions are made in the circumstances of a health emergency, such as former Justice Ruth Bader Ginsberg's battles with colon and pancreatic cancer during her tenure on the Court.

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U.S. District Judge Fred Biery, who was notified Saturday morning of Scalia's death, told the The San Antonio Express-News "As far as the details, I think it's pretty vague right now as to how." Biery continued, "My reaction is it's very unfortunate." Reactions to Scalia's death have poured in since the news first broke Saturday, with Supreme Court Chief Justice John Roberts expressing his deepest sympathies to Scalia's family. Former President George W. Bush, Texas Gov. Greg Abbott, and several of the current presidential hopefuls have also released statements in the wake of Scalia's passing. President Barack Obama is expected to release an official statement later on Saturday.

With a vacancy on the bench of the highest court in the nation, many have been left wondering who will replace Scalia. Senate Majority Leader Mitch McConnell said in a statement that "this vacancy should not be filled until we have a new president." Meanwhile, Senate Minority Leader Harry Reid issued a statement saying that "the Senate has a responsibility to fill vacancies as soon as possible." Currently, Obama has the executive authority to appoint someone to fulfill Scalia's seat on the Supreme Court before his term ends in 2017 — whether or not Obama will actually do so remains to be seen.

This story is developing.