Fallen Patriots star Aaron Hernandez is at the center of a probe into an unsolved 2012 double slaying in Boston while Dartmouth jail officials are scouring the troubled tight end’s wild array of tattoos for any gang ink links, the Herald has learned. “We’ll be looking at his tattoos to see if there are any symbols that affiliate with gangs,” said Bristol County Sheriff Thomas Hodgson, who met with Hernandez yesterday after his bail was denied by a Fall River judge. “We have to always be vigilant around security and not place him somewhere where there are rival gang members.” A Los Angeles gang expert told the Herald last night if it’s proven Hernandez does have gang ink, he’s in danger. “Hernandez could be a very appealing target for someone who wants to make a reputation for himself,” said Jorja Leap, adjunct professor of social welfare at UCLA. “The sheriff needs to be extra careful with someone like Hernandez.” Leap, author of a book on her gang work, said she’s studied Hernandez’s tattoos, and they appear decorative — with an emphasis on “sleeves” of ink up and down his arms. But what she can’t see could prove critical. Gang tattoos are often “crude,” she said, and direct — such as “LK” for Latin Kings or devil horns for the MS-13 gang. “It could also be a gang saying, like ‘smile now, pay later,’ ” Leap said, adding Hodgson’s team 
will spot it if they see it. Hernandez, who was cut by the Pats after he was charged with executing 27-year-old Odin L. Lloyd in North Attleboro last week, is in the jail’s medical unit where he’s undergoing mental and physical testing, as well as a “security screening,” which includes meeting with the jail’s gang intelligence unit. Hernandez, 23, was pegged as a top pick in the 2010 National Football League draft but his stock plummeted — reportedly because of character concerns, including rumors of gang affiliation — and he fell to the Patriots in the fourth round.