Donald Trump has been briefed by US intelligence on threats from Iran to assassinate him, his campaign said.
The Republican presidential candidate was briefed "regarding real and specific threats from Iran to assassinate him in an effort to destabilize and sow chaos in the United States", the campaign said in a statement.
It did not elaborate on the claims, and it was not immediately clear if the threats it referred to were new or had been previously reported.
The Iranian government did not immediately respond to a request for comment, but Tehran has previously denied US claims of interfering in American affairs.
"Intelligence officials have identified that these continued and coordinated attacks have heightened in the past few months," Trump campaign communications director Steven Cheung said in the statement.
"Law enforcement officials across all agencies are working to ensure President Trump is protected and the election is free from interference," he added.
The BBC has approached the Office of the Director of National Intelligence in the US for comment.
It comes after Mr Trump survived an assassination attempt on 13 July, when he was wounded and another person was killed in a shooting at a rally in Pennsylvania. No motive has been determined and it remains under investigation.
In the days after, US media reported that officials had received intelligence of an alleged Iranian plot against the former president. Iranian officials at the time rebuffed the allegations as "malicious", the BBC'S US partner CBS news reported.
"If they do 'assassinate President Trump,' which is always a possibility, I hope that America obliterates Iran, wipes it off the face of the Earth - If that does not happen, American Leaders will be considered 'gutless' cowards!" Mr Trump wrote on his Truth Social platform at the time.
Then on 15 September, a Secret Service agent spotted a rifle poking through a fence at Trump International Golf Club in West Palm Beach. The agent opened fire as Mr Trump was playing a round of golf.
US prosecutors have charged Ryan Wesley Routh, a man arrested near the golf course, with the attempted assassination of a presidential candidate.
There has been no suggestion Iran was involved in either case.
Last month, the Trump campaign said some of its internal communications had been hacked and suggested it was targeted by Iranian operatives.
