Halle Berry's Custody Case Turns Ugly

The actress and her ex, model Gabriel Aubry, have gone from friendly co-parents to fighting over daughter Nahla

After splitting last April, Halle Berry and Gabriel Aubry seemed determined to remain peaceful co-parents of their daughter Nahla, who will turn 3 in March.

But tensions rose quickly, and now Nahla’s parents are gearing up for a custody battle that’s already turning nasty, with ugly accusations flying.

“Once they broke up he became verbally threatening to Halle,” Aubry’s former friend and business partner Stephane Bibeau tells PEOPLE in this week’s cover story. “He is a vindictive guy.” Bibeau and other sources close to Berry, 44, claim that Aubry, 35, has used a racial slur against her.

PHOTOS: Halle Berry & Nahla: Two of a Kind

“That’s just unacceptable,” a source close to the actress says.

“The fact is that Gabriel is a caring father who shares custody of Nahla,” according to a statement released by Aubry’s rep Tuesday.

Friends of the French-Canadian model – who filed court papers on Dec. 30, seeking formal recognition as Nahla’s father and joint legal and physical custody – expressed support for him.

“I never saw someone more dedicated to their child,” a friend of Aubry’s says.

Adds a source close to Aubry: “From the beginning, Halle kind of had the upper hand because she was essentially supporting all of them for the most part. Gabriel never liked how that felt. Their split was tough because they’re both so involved in raising Nahla, and neither ever wanted to give that up.”

Berry sees it differently. Her rep issued a statement to PEOPLE on Monday, expressing her “serious concerns for her daughter’s well-being while in the care of her father.”

“The only reason Gabriel is seeing Nahla right now is because the court hasn’t made a decision yet,” says a source close to the actress. “If it were up to Halle, he wouldn’t be seeing her at all without some sort of supervision.”

For much more on this story, pick up this week’s issue of PEOPLE, on newsstands Friday

PHOTOS: The Berry-Aubrys: The Way They Were