The gloves are off in the divorce battle between Marc Anthony and Jennifer Lopez. Us Weekly reports that Anthony is livid over Lopez’s new love with dancer Casper Smart — and is trying to punish her through gaining custody of their twins.

The news is a bit of a bombshell, seeing as up to this point the split seemed civil and amicable. Us says that the photos of Lopez, 42, and Smart, 24 in Hawaii over Thanksgiving with three-year-old twins Max and Emme sent Anthony over the edge. A source told the mag that when Anthony saw the paparazzi snaps, he “hit the roof. It caused a huge blowup.”

This isn’t the first report of Anthony’s upset antics following his break up with Lopez. He’s prone to tantrums over her new romance, and he burst into tears onstage following their summer split.

While Anthony forbade Smart from driving his kids around — somewhat understandably, given Smart’s drag racing arrest — this move is coming as a shock. Though the couple had already made arrangements for Lopez to have primary custody of the tots, Anthony’s move is said to be vindictive. “He wants to make Jennifer suffer because she’s having fun with someone new,” a source said, “and he knows this will hurt her on the deepest level.” Cold!

However, the famously feisty Lopez won’t take Anthony’s behavior lying down. One of Jenny from the Block’s pals told Us that the ‘American Idol‘ judge is “ready to smash him if he tries anything … It’s getting vicious.”

While we applaud both of their devotion to their kids, going at each other’s throats can’t be good. Here’s hoping that both Lopez and Anthony keep Max and Emme’s best interests at heart and can resolve their issues respectfully.