U.S. Supreme Court Justice Antonin Scalia was found dead Saturday, CBS News has confirmed. A spokesperson for the U.S. Marshals Service said he appeared to die of natural causes.

According to the San Antonio News-Express, which was first to report his death, Scalia was found dead in his room at a West Texas resort.

Scalia, 79, was one of the staunchest conservative members of the court. He was nominated in 1986 by President Ronald Reagan and is the longest-serving member on the court.

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He championed the philosophy of "orginalism," meaning he interprets the Constitution according to what he believes the original authors intended over 200 years ago.

In a 2008 interview with "60 Minutes," he told correspondent Lesley Stahl that he believes the Constitution is an "enduring" document he wants to defend.

"It's what did the words mean to the people who ratified the Bill of Rights or who ratified the Constitution," Scalia said.

"But you do admit that values change? We do adapt. We move," Stahl asked.

"That's fine," he answered. "And so do laws change. Because values change, legislatures abolish the death penalty, permit same-sex marriage if they want, abolish laws against homosexual conduct. That's how the change in a society occurs. Society doesn't change through a Constitution."

In a statement on behalf of the Supreme Court and retired Justices, Chief Justice John Roberts called Scalia, "an extraordinary individual and jurist, admired and treasured by his colleagues."

"His passing is a great loss to the Court and the country he so loyally served. We extend our deepest condolences to his wife Maureen and his family," he added.

Scalia's replacement to the court would be President Obama's third nomination. He previously nominated Justices Sonia Sotomayor and Elena Kagan. But CBS News Chief Legal Correspondent Jan Crawford said it is unclear whether the Republican-held Senate will entertain a nomination from Mr. Obama or wait for a new president to be elected this November.

"It could be very unlikely that President Obama that will get that nomination," Crawford said. "This court could remain with eight justices until the next president takes office. I think that's very unclear what will happen."

"This vote will change the balance of the Supreme Court if a liberal is nominated," she added.

Mr. Obama was informed of Scalia's death Saturday afternoon. He and Michelle Obama extended their deepest condolences to Justice Scalia's family.

Senate Majority Leader Mitch McConnell, R-Kentucky, suggested that the Senate will not entertain a nomination from Mr. Obama.

"The American people‎ should have a voice in the selection of their next Supreme Court Justice. Therefore, this vacancy should not be filled until we have a new President," he said in a statement.

And Sen. Ted Cruz, R-Texas, one of the 2016 presidential candidates, said the responsibility should fall to the next president.

Justice Scalia was an American hero. We owe it to him, & the Nation, for the Senate to ensure that the next President names his replacement. — Ted Cruz (@tedcruz) February 13, 2016

But Senate Minority Leader Harry Reid, D-Nevada, argued that President Obama "can and should send the Senate a nominee right away."

"With so many important issues pending before the Supreme Court, the Senate has a responsibility to fill vacancies as soon as possible," Reid said in a statement Saturday. "It would be unprecedented in recent history for the Supreme Court to go a year with a vacant seat. Failing to fill this vacancy would be a shameful abdication of one of the Senate's most essential Constitutional responsibilities."

Democratic presidential candidate Hillary Clinton added her own admonishment for those calling to keep Scalia's seat vacant.

"The Republicans in the Senate and on the campaign trail who are calling for Justice Scalia's seat to remain vacant dishonor our Constitution," she said in a statement. "The Senate has a constitutional responsibility here that it cannot abdicate for partisan political reasons."

Scalia, the son of Italian immigrants, was born in Trenton, New Jersey and raised in the Queens neighborhood of New York City. He attended at Georgetown University and Harvard Law School.

Former President Bush said in a statement that Scalia was a "towering figure and important judge on our Nation's highest court. He brought intellect, good judgment, and wit to the bench, and he will be missed by his colleagues and our country."

CBS News Justice Department Producer Paula Reid contributed to this story.