WASHINGTON — The Iranian hanging of scientist Shahram Amiri — referenced in Hillary Clinton’s e-mail exchanges — could be just the beginning of the “human cost” of Clinton’s private e-mail server, a Donald Trump surrogate said Monday.

“Hillary Clinton’s extreme carelessness in the use of private devices and a private server has placed US national security at high risk,” retired Lt. Gen. Michael Flynn told Fox News.

“It’s just sad and it’s just tragic and we are going to see more of these kinds of things come up in the coming weeks and months just because of Hillary Clinton’s extreme carelessness in what she did.”

“There’s going to be a human cost to that [private e-mail server]. We’re probably seeing that . . . with this guy that was killed over in Iran,” added Flynn, the former director of the Defense Intelligence Agency.

Amiri, a nuclear scientist, was hanged in Iran for providing information about the country’s nuclear program to the US.

He lived in the US briefly in 2010, when Clinton State Department staffers referenced Amiri and his desire to go back to Iran in two e-mail exchanges on her private server, calling him “our friend.”

Clinton’s campaign rejected allegations she had anything to do with Amiri’s execution as “baseless,” “desperate” and “absurd.”

“The Trump campaign has never met a conspiracy theory it didn’t like,” said spokesman Jesse Lehrich.