By Julie Jordan

Originally posted Monday April 21, 2008 07:30 PM EDT

Diane Farr, who stars on CBS's Numb3rs, is pregnant with twins, a source close to the actress tells PEOPLE.

Farr, 38, and her husband, marketing executive Seung Yong Chung, already have a 1-year-old son, Beckett Mancuso Chung.

The actress plans to leave Numb3rs at the end of the season in order to spend the next year preparing for her twins and working on a TV series with Rescue Me writer Peter Tolan, according to the source. The two are currently in negotiations with a network but no deal has been finalized.

People.com