'Teen Mom' Amber Portwood Back In Jail: REPORT

12/19/2011 04:04 pm ET

There's more drama for "Teen Mom" Amber Portwood. She's back in the slammer after a judge issued a warrant for her arrest, TMZ reports.

She's currently biding her time in Indiana's Madison County jail until a scheduled court date on Jan. 13.

It's not exactly clear why Portwood was arrested yet again, but sources tell TMZ that it's not related to her probation violation, which was reported last week after she allegedly got into a physical altercation in an Indiana IHOP.

"She was drunk, and there was another girl in the restaurant who had been drinking too and apparently said something about Amber to her friend," a source reportedly told Star magazine about the incident. "She told the girl, 'You don't know anything about me! I'm gonna whup your ass!' They just attacked each other."

In June, Portwood was sentenced to two years in jail after pleading guilty to two counts of felony domestic battery against the father of her child, Gary Shirley. However, her sentence was suspended and she was put on two years probation.

Portwood and Shirley were featured on MTV's "Teen Mom" reality show. They have one daughter, Leah, 3.