Last Updated 11:44 a.m. ET
PEORIA, Ariz. - The Secret Service is investigating a picture that was posted on an Arizona police officer's Facebook page in which an image of President Barack Obama appears to have been used for target practice.
The Peoria Police Department is also investigating Police Sgt. Patrick Shearer and a picture that was uploaded on Jan. 19 showing several young men in the desert holding various weapons (including assault rifles and a revolver) and holding up a T-shirt with President Obama's likeness on it.
The shirt appeared riddled with bullet holes.
The picture was online while the president was visiting Arizona earlier this week, but was removed from the sergeant's page on Thursday after inquiries were made to the Peoria Police.
"We received information about a possible policy violation today involving one of our employees," Peoria Police spokesman Jay Davies told CBS Affiliate KPHO.
Davies said Peoria Police were contacted by the Secret Service.
The Secret Service confirmed to KPHO that it has launched an investigation surrounding the picture.
A Secret Service official confirmed to CBS News that an investigation is underway, saying, "We're aware of the incident and we are taking the appropriate follow-up steps. We recognize that people have the right to free speech, but we also have the right to determine what someone's intent is.
"When we get information that shows someone has an unusual direction of interest in one of our protectees we take the appropriate follow-up steps."
Sources tell CBS News homeland security correspondent Bob Orr that there is no "threat" attached to the picture, or that the students in the photo or the officer who took the photo intended any threat. The picture apparently is months old and was just recent posted.
Shearer has been with the police in Peoria (a suburb of Phoenix) at least 14 years, and will remain on duty while the department determines if he violated its social media policy, which says, "Posting information regarding off-duty activity that may tend to bring an officer's reputation into question is strongly discouraged."
"We seek to maintain a positive image and ensure that we're always holding our employees to that standard," Davies said. Discipline for violating the policy varies depending on the situation, Davies told KPHO correspondent Lindsey Reiser.
The New York Times reports Shearer was decorated in 2007 for helping to save a driver trapped in a burning vehicle.
The Times also reports that the same image was posted on the Facebook page of one of the young men holding a gun in the photo, identified as a student at Centennial High School in Peoria. School officials are now conducting their own investigation.