FBI Director Kash Patel said the bureau is "assisting local authorities and putting all necessary resources at their disposal" regarding the death of Republican Senator Lindsey Graham, while four sources told CNN that investigators currently have no indications that the death was due to unnatural or criminal causes.

One source explained that local police are conducting a routine review following the death, while the FBI has offered its resources if needed.

CNN reported that it asked the bureau to clarify Patel's post and whether there was any other reason for his involvement in the procedures related to Graham's death.

Patel has previously faced criticism for posts on platform "X" that caused confusion regarding prominent investigations, including the early stages of the investigation into the assassination of conservative activist Charlie Kirk.

Nancy Mace considers running for his seat

In a development following Graham's death, Politico reported that Republican Representative Nancy Mace is considering running for the Senate to fill the seat left vacant by the Republican senator's death, according to two sources familiar with her consultations who spoke on condition of anonymity.

The two sources said Mace plans to begin conducting preliminary polls this week to explore her candidacy prospects, and she still retains funds in her federal campaign account from her previous House races.

Mace is scheduled to leave her House seat early next year after giving it up to run for governor of North Carolina this year, but she failed to win, finishing fifth in the Republican primary.

After that result, her political future seemed unclear, but the Senate vacancy may give her a new opportunity to remain in Washington.

This would not be her first attempt to reach the Senate; she previously ran in the 2014 Republican primary against Graham, but finished fifth by a wide margin.

Disagreements with Trump could hinder her candidacy

Despite that, Mace may face strong opposition from US President Donald Trump after she clashed with him over her demand for the release of files on Jeffrey Epstein, the late convicted sex offender billionaire, along with other files.

The US president had made clear during the South Carolina governor's race that he did not want Mace to win, when he endorsed one of her opponents in the primary. According to two of the president's allies, his inner circle is already rekindling those disputes in private discussions about the future of Graham's Senate seat.

"Short sudden" illness

Graham's office announced Sunday that he died at age 71 after a "short sudden" illness, and said his family "appreciates the prayers for him at this time and requests privacy during this extremely difficult period."

Graham served as chairman of the Senate Budget Committee and was seeking a fifth six-year term in November's election. He was one of the most prominent senators and an influential voice within the Republican Party on defense and international affairs.