Josh Hartnett and Tamsin Egerton Credit: Michael Kovac/Getty Images

Josh Hartnett is a dad! The Black Hawk Down actor and his girlfriend, Tamsin Egerton, have welcomed their first child together, Us Weekly can confirm.

The couple were photographed leaving St. Mary’s Hospital in London on Tuesday, Dec. 1, and the proud papa toted their little one in a baby carrier.

Us reported in July that the Pearl Harbor actor, 37, and the actress, 27, were expecting their first child together. Hartnett met the British star in 2011 on the set of The Lovers. The two became romantic a year later and were first spotted out together in May 2013.

"It was just a natural thing that happened," a source told Us at the time. "He said she was really nice. They seem to just really enjoy each other's company. And he thinks she's gorgeous, of course."

Sign up now for the Us Weekly newsletter to get breaking celebrity news, hot pics, and more delivered straight to your inbox!