Iran said on Thursday that accusations it had targeted former U.S. officials were baseless, after former U.S. President Donald Trump implicated Iran, without offering evidence, in assassination attempts against him.

"It is obvious that such accusations are just a part of creating the election atmosphere in the U.S...., and not even worth a response," Iranian foreign ministry spokesperson Nasser Kanaani said in a statement.

Trump, the Republican candidate to return to the presidency, said Wednesday that Iran may have been behind recent attempts to assassinate him and suggested that if he were president and another country threatened a U.S. presidential candidate, it risked being "blown to smithereens."

"There have been two assassination attempts on my life that we know of, and they may or may not involve, but possibly do, Iran, but I don’t really know," Trump said at an event a pipe-fittings plant in Mint Hill, North Carolina.

Trump made his remarks after U.S. intelligence officials briefed him a day earlier on "real and specific threats from Iran to assassinate him," according to his campaign.

Federal authorities are probing assassination attempts targeting Trump at his Florida golf course in mid-September and at a rally in Pennsylvania in July. There has been no public suggestion by law enforcement agencies of involvement by Iran or any other foreign power in either incident.