Lindsey Graham, R-S.C., who was elected to the US Senate in 2003 and was a close political ally of President Donald Trump, has died, his office confirmed early Sunday. He was 71.

Axar.az reports, citing NBC News, Graham died Saturday night “from a brief and sudden illness,” his office said in a statement.

“Senator Graham’s family appreciates prayers at this time and asks for privacy during this incredibly difficult period,” the statement continued.

Graham was chairman of the Senate Budget Committee and was seeking a fifth six-year Senate term in November. He was one of the most well-known members of the chamber and a key voice within the party on defense and international affairs.

Emergency personnel responded to a call for “cardiac arrest” at Graham’s Capitol Hill home on Saturday night, according to police scanner audio obtained by NBC News.