WEST MONROE, La. -- Secret Service is determining whether an investigation is needed after somebody urged Rick Santorum to "pretend it's Obama" while he was test-firing a weapon at a campaign stop. 

Santorum stopped at the Ouachita Parish Sheriff Office Shooting Range in West Monroe, La., on Friday morning.

As Santorum squeezed the trigger of an M-19 Colt pistol, the onlooker screamed out, "pretend it's Obama."

Secret Service representative Lou Velez said, "We would look into it, we would definitely look into it."

Speaking to reporters after his event, Santorum called the outburst "absurd."

"No, we're not pretending it's anybody but shooting pistols," he said. "It's a very terrible and horrible remark and I'm glad I didn't hear it."