Two construction workers were killed Tuesday after falling about 65 feet from a Upper West Side church, prompting the Department of Buildings to issue a stop-work order at the site.

Authorities say Brett McEnroe, 49, of Dover Plains, N.Y. and Roy Powell, 51, of New Paltz, N.Y. were working on top of an elevator shaft on the seventh floor of 150 West 83rd Street when they fell – landing on scaffolding on the third floor around 10:30 a.m. Tuesday.

The two upstate men, who were part of a four-man crew to make the Redeemer Presbyterian Church taller, were rushed to area hospitals but were later pronounced dead. Both worked for Weir Welding and Cross County Erectors.

City and federal officials at the scene were investigating what caused the fall.

"During the steel erection there were two beams and it's a possibility that a beam rotated during that task. When it rotated there was no fall protection and they fell," said Buildings Commissioner Robert LiMandri.

Regulations state that workers need to be protected from falls by a harness, an extra platform or a net.

"At the moment, we don't see evidence of that," said LiMandri.

Officials said the construction company, FJ Sciame, had previous violations at the site, but were not directly related to work being performed on Tuesday.

Both the construction company and the owner of Redeemer Church said they immediately reported the incident to the DOB and were fully cooperating with the investigation.

The New York City Police Department said Tuesday no criminality was suspected.