Michelle Trachtenberg, the actress who rose to fame as a precocious child star in “Harriet the Spy” and went on to have memorable roles on TV shows including “Gossip Girl,” has died, according to the New York City police.

Michelle Trachtenberg—the film and television actor known for roles in Buffy The Vampire Slayer, Gossip Girl, Harriet The Spy, and Ice Princess—had died. Her death was confirmed by ABC News. The outlet reports that she had undergone a liver transplant recently and is believed to have died from natural causes. She was 39.

The NYPD confirmed to PEOPLE that Trachtenberg was found "unconscious and unresponsive" in her Manhattan apartment on Wednesday, Feb. 26 and pronounced dead at the scene