Mel Gibson & Oksana Grigorieva Split

Mel Gibson and Oksana Grigorieva have split after over a year of dating, People reports.

"They just drifted apart," says a close friend of the couple who are pictured above last month. "They’re both working hard on their careers and trying to raise a sweet baby together. They're still friends and they'll both raise Lucia together."

The Lethal Weapon star and Oksana, a musician-singer, welcomed their daughter Lucia on October 30, 2009.

Gibson is busy in Mexico filming How I Spent My Summer Vacation, and Grigorieva is working on her music career. Next week, she will perform a charity concert in Russia to benefit Grant Life.

In addition to Lucia, Gibson, 54, has seven children (six sons and a daughter) with his estranged wife Robyn. Grigorieva also has a son, Alexander, with her former boyfriend, actor Timothy Dalton.