Idris Elba welcomes a baby son with girlfriend Naiyana Garth

Idris Elba and his girlfriend Naiyana Garth welcomed a baby boy on Thursday, the actor announced Friday on Twitter.

“My Son Winston Elba was born yesterday..Truly Amazing :-),� he wrote, including a black-and-white picture of the new cutie’s tiny hand wrapped around his dad’s fingertip.

The British actor, a 2012 Golden Globe winner for “Luther,� went public about his relationship with makeup artist Garth last November, though they’d reportedly been dating for several months already. Rumors that Garth was pregnant emerged around the same time.

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Winston’s birth has to be a moving experience for Elba, 41, who in 2010 welcomed a child he thought was his son, only to find out after taking a paternity test that he wasn’t the child’s father.

“The celebration of having a son — from a man’s perspective, it’s massive,� he told GQ in its October issue, commenting on the 2010 events.

“The Wire� alum also has an 11-year-old daughter, Isam, from his marriage to Dormowa Sherman, a Liberian actress. Isam lives in Atlanta, and he said he doesn’t get to see her very much outside of the occasional meet-up in a hotel or another temporary space, in part because he has no traditional home.

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“I’m like a gypsy, man,� Elba told the men’s magazine. “We’ve had this relationship since she was 1. She’s always on the road.�

Last month, the “Pacific Rim� actor was reportedly in final negotiations to voice the notorious tiger Shere Khan in Disney’s “Jungle Book.�

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