US Sen. Lindsey Graham dies at 71

U.S. Sen. Lindsey Graham, R-S.C., has died at the age of 71.  Graham's office released a statement early Sunday morning saying he died following a "brief and sudden" illness.

His office said his family "appreciates prayers at this time and asks for privacy during this incredibly difficult period."

Lindsey Graham's cause of death

According to Graham's office, preliminary findings show he died of aortic dissection due to arteriosclerotic cardiovascular disease.

"The death certificate will be PENDING until all the toxicological and microscopic testing are finalized and at that point the death certificate will be updated to reflect the cause of death and appropriately classify the manner of death," his office said. 

Lindsey Graham's career

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Graham served in the U.S. Senate since 2003 after first being elected in 2002 and was seeking a fifth Senate term after winning the Republican primary last month.

During his more than three decades in elected office, Graham served on several influential Senate committees, including Appropriations, Judiciary, and Environment and Public Works.

Before joining the Senate, he represented South Carolina's 3rd Congressional District in the U.S. House of Representatives. Graham remained active in foreign policy until his death. He met with Ukrainian President Volodymyr Zelenskyy in Kyiv on Friday and was scheduled to appear on NBC's "Meet the Press" on Sunday.

A veteran of the U.S. Air Force, Air National Guard, and Air Force Reserve, Graham retired as a colonel in 2015 after 33 years of military service, including deployments during the Gulf War, Iraq, and Afghanistan.

Funeral arrangements have not yet been announced.

President Donald Trump paid tribute to Graham on Truth Social, calling him "a true American Patriot" and saying he would be "greatly missed." South Carolina Gov. Henry McMaster also honored Graham, describing him as an "irreplaceable" leader and a loyal friend.

"I just can’t believe it," the president told NBC's "Meet the Press." "He was like a member of the family."

Graham often advised Trump on foreign affairs, particularly on matters pertaining to Israel, Ukraine and Iran. He was a frequent visitor at the White House.

"At the end of a particularly thrilling and rollicking meeting in the Oval Office, Lindsey Graham turned to the room and said: 'I’ve never had this much fun in my life,’" deputy White House chief of staff Stephen Miller wrote on X. He said such gatherings "were filled with camaraderie, kinship and uproarious laughter."

Trump recalled that during his last conversation with Graham, he told his friend, "We’ll see you soon, come over anytime you want."

Trump said he's ordered all American flags to be lowered to half-staff until 6 p.m. Saturday.