A doctor plunged to his death at his former NYU residence hall in Manhattan on Monday afternoon, sources said.

The man jumped off the roof of Vilcek Hall on East 26th Street around 2 p.m., falling 26 stories and landing in a gated parking lot directly behind the dorm.

Witnesses walking down the street watched the tragedy unfold.

“My friend and I were walking and we heard like a thud or a boom sound,” said Albert Camacho, 50, who leaves nearby. “We already knew, We saw people looking up.”

Camacho said the scene was incredibly gory, saying, “He exploded. I think his head opened up. There was blood.” The man’s brown dress shoes remained on the pavement for at least an hour as authorities searched the building for any evidence into what drove him to jump.

Police said he used to live in the building, but had recently moved uptown after completing his residency in May through NYU’s School of Medicine.

Cops told The Post he left his keys and NYU ID on the roof of Vilcek Hall, which was recently converted to residencies for NYU’s post-doc students and nurses. NYU’s School of Medicine’s student health center is housed on the ground floor.

His name has not yet been released as authorities are still trying to notify his next of kin.