(CNN) -- Los Angeles police have launched an internal investigation to determine who leaked a picture that appears to show a bruised and battered Rihanna.
Rihanna was allegedly attacked by her boyfriend, singer Chris Brown, before the Grammys on February 8.
The close-up photo -- showing a woman with contusions on her forehead and below her eyes, and cuts on her lip -- was published on the entertainment Web site TMZ Thursday. TMZ said it was a photo of Rihanna.
Twenty-one-year-old Rihanna was allegedly attacked by her boyfriend, singer Chris Brown, on a Los Angeles street before the two were to perform at the Grammys on February 8.
"The unauthorized release of a domestic violence photograph immediately generated an internal investigation," an L.A. police spokesman said in a statement. "The Los Angeles Police Department takes seriously its duty to maintain the confidentiality of victims of domestic violence. A violation of this type is considered serious misconduct, with penalties up to and including termination."
A spokeswoman for Rihanna declined to comment.
The chief investigator in the case had told CNN earlier that authorities had tried to guard against leaks. Detective Deshon Andrews said he had kept the case file closely guarded and that no copies had been made of the original photos and documents.
Brown was arrested on February 8 in connection with the case and and booked on suspicion of making criminal threats.
Authorities are trying to determine whether Brown should face domestic violence-related charges.
Brown apologized for the incident this week.
"Words cannot begin to express how sorry and saddened I am over what transpired," the 19-year-old said in a statement released by his spokesman. "I am seeking the counseling of my pastor, my mother and other loved ones and I am committed, with God's help, to emerging a better person."
CNN's Brittany Kaplan contributed to this report.