A 51-year-old man was suspended on a scaffold as he did facade repair work on a brick building in Manhattan when he was hit in the head by a heavy stone slab.

There was a cry for help from this man.

“I’m going to fall!” a man repeatedly said in Spanish as he clung to the scaffolding that dangled against a building on East 50th Street in Manhattan.

The man had been struck in the head and bloodied by a heavy piece of molding while repairing the building’s masonry. Although authorities rescued him from the scaffold, he would die later at a hospital at 51 years old.

Amid New York’s towering buildings, where scaffolding is so common it seemingly blends into the design, the man’s death offered a reminder of the risks faced by workers in a city under constant construction.

The man had been outside the 14-story residence at 311 East 50th Street when he was struck by a coping stone that had been removed to anchor the suspended scaffold, a Fire Department official said.

Witnesses saw the man clinging to the structure and heard his shouts.

“He was holding on for his life,” said Rodrigo Galindo, 52, who was delivering food nearby. “I was rooting for him.”

Firefighters climbed a ladder to reach the man, who by that point appeared to have lost consciousness, Mr. Galindo said. They broke a window and pulled the man inside, as a co-worker on the scaffold stood motionless, a witness said.

Jimmy Khan, 50, an employee at a nearby deli, watched as the man was carried away on a gurney. “I had to look away,” Mr. Khan said.

The man was taken to NewYork-Presbyterian Hospital, where he died. His name was not released, pending family notification. It was unclear if he had been wearing a hard hat or harness.

A second worker on the scaffolding at the time of the incident was not injured but was taken to the hospital for observation.