(CNN) -- Are clues to alleged murders hidden in tattoos on the right forearm of former New England Patriots tight end Aaron Hernandez?
Police and prosecutors have charged Hernandez, 24, with two counts of first-degree murder in the July 2012 killings of two men in Boston. They are now seeking the help of tattoo artists who may have inked him after the homicides.
Hernandez is in jail awaiting trial in the separate 2013 slaying of Odin Lloyd.
A grand jury indicted Hernandez last week in the 2012 shooting deaths of Daniel de Abreu and Safiro Furtado, and he is to be arraigned on the new charges on May 28.
"Boston Police and Suffolk prosecutors are seeking assistance from tattoo artists who may have inked Aaron Hernandez in the aftermath of the 2012 homicides of Daniel de Abreu and Safiro Furtado," the Suffolk County district attorney said in a statement.
The artists being sought for potential evidence are considered witnesses and are not accused of any wrongdoing, the statement said.
Suffolk County District Attorney Daniel Conley has said de Abreu and Furtado were "ambushed and executed" while driving home along Shawmut Avenue in Boston's South End early on July 16, 2012.
In addition to the two counts of first-degree murder, Hernandez has been charged with three counts of armed assault with intent to murder and one count of assault and battery by means of a dangerous weapon, the district attorney said. The latter four counts reflect shots fired at three people, one of whom was wounded, inside the car that de Abreu and Furtado were in, Conley said.
Conley said that Hernandez was driving an SUV that pulled up alongside de Abreu and Furtado's car near a nightclub and that the former football star fired a .38-caliber revolver at them.
Investigators are hoping to speak with the artist or artists who inked Hernandez with specific tattoos on his right forearm between February 2012 and June 2013, the statement said. During that time, Hernandez is known to have traveled to Hermosa Beach, California; Bristol, Connecticut; Palm Beach and Miami, Florida; Boston; and Rhode Island.
"In order not to taint any potential statements, authorities are not publicly describing the specific tattoos or the nature of the inquiry -- only that the artists may have made observations of evidentiary value in the pending Suffolk County murder prosecutions," the statement said.
In the other case, Hernandez was charged with first-degree murder and weapons charges in connection with the shooting death of Lloyd, a 27-year-old semipro football player, in North Attleboro, Massachusetts, about a mile from Hernandez's home. Lloyd was dating a sister of Hernandez's fiancee's.
Anyone with more information is asked to contact Boston Police Sgt. Detective Marc Sullivan at 617-343-5839.
Hernandez's jail visitors have included his fiancee and his cousin, Tanya Cummings Singleton, both of whom face charges in connection with the Lloyd homicide, court papers revealed in February.
Last week, prosecutors announced that Singleton was charged with criminal contempt of court in connection with the de Abreu and Furtado slayings. She is to be arraigned June 2 on an additional indictment for criminal contempt of court.