Story highlights A Trump adviser called for Hillary Clinton to be "shot for treason" over Benghazi

Cotton said: "That kind of rhetoric has no place in our politics"

(CNN) The US Secret Service is investigating an informal adviser to Donald Trump's presidential campaign after he called for Hillary Clinton's execution.

Al Baldasaro, a New Hampshire state representative, told radio host Jeff Kuhner Tuesday that Clinton "should be put in the firing line and shot for treason."

"The U.S. Secret Service is aware of this matter and will conduct the appropriate investigation," said Shawn L. Holtzclaw, a spokesman for the Secret Service.

Trump spokeswoman Hope Hicks told CNN the campaign "does not agree with those statements."

She declined to characterize Baldasaro's role with the campaign or whether he would continue to travel with Trump on occasion.

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