It was lunchtime, and the building - a long-vacant Blockbuster Video store on Route 38 in Cherry Hill - had been nearly razed to make way for a new Super Wawa.
But things went awry at 12:31 Friday, when a cinder block wall and a metal roof collapsed during the demolition, killing one worker and sending another to the hospital.
The dead worker was a male day laborer who had been employed by a subcontractor for just two weeks, federal officials said Friday night.
An official with knowledge of the accident said the victim was evidently inside what remained of the building even as its walls were being knocked down. The roof collapsed when one of the last two walls was demolished, killing him, the official said.
Authorities had not released the names of the dead or the injured worker Friday night. Township documents identified Carl R. Pursell Inc. of Berlin as the contractor at the site. Mancuso Contractors Inc. of Maple Shade was the subcontractor. A third person was on the site at the time but was not injured.
Pursell had obtained the proper permits. The township conducted a sewer inspection of the site Monday. Public Service Electric & Gas notified the project on May 27 that all gas lines had been closed and the site was safe for demolition.
Cherry Hill Fire Director Patrick Kelly said the building, at the edge of the Walmart Plaza near Cuthbert Boulevard, was "98 percent down" when the accident occurred.
"For some reason, it came down," Kelly said.
The victim remained in a six-foot-deep trench at the site for two hours, until firefighters started heaving large cinder blocks out of the way to pull him from the rubble.
Officials from the Camden County Prosecutor's Office and the federal Office of Safety and Health Administration were on the site investigating. An OSHA spokeswoman said the agency was probing Pursell and Mancuso in connection with the accident.
The second worker, who Kelly said was operating the excavator when the wall fell, was taken to Kennedy University Hospital-Cherry Hill with chest pains. Kelly said the man was shook up but expected to survive.
Kelly could not say if the machine played a role in the collapse.
"The wall came down. One employee was on the ground; another was in the excavator," Kelly said. "You make your assumptions."
A Wawa Inc. spokeswoman said those involved were a "longtime general contractor and subcontractor," and said the death was the first such incident in its 50-year history of building more than 1,000 stores.
"Our hearts and prayers go out to the family and friends of the victim of this tragic event," Lori Bruce said in a statement. "We are doing everything we can to support those involved and the authorities in their investigation."
A woman reached at a phone number for Pursell said she could not confirm if the business was involved. Subsequent attempts to reach company officials were unsuccessful.
An address listed for Mancuso is a two-story brick house just off Route 38 in Maple Shade. No one answered the door. Reached by phone, the Mancuso family declined to comment.
Pursell and Mancuso have been cited for OSHA violations.
OSHA fined Mancuso nearly $3,400 in 1999 and 2000. Details of the violations were unavailable.
Pursell was fined more than $15,000 for violations from 2007 to 2013, according to OSHA documents.
In 2009, a carpenter working for Pursell installing roof trusses in Berlin was hospitalized after falling 15 to 20 feet, according to OSHA. Accident investigators found the worker was not wearing safety equipment that would have protected him in a fall. The firm was fined $4,200.
Inquirer staff writers Kristen A. Graham and Dylan Purcell contributed to this article.