The U.S. Occupational Safety and Health Administration is investigating the cause of a fatal tower crane collapse at the University of Texas at Dallas campus in Richardson on July 7, but experts familiar with the accident are already pointing to problems with the dismantling process.

Crews at the site of the new $60-million Arts and Technology Building being built on the campus were disassembling the crane when it collapsed, killing two workers. The workers were Thomas Fairbrother Jr., 58, of Austin and Terry Weaver, 50, of Grand Saline, according to the Collin County Medical Examiner’s office. Both worked for Harrison Crane and Hoist, Grand Prairie, Texas, sources say. Hunt Construction Group is the general contractor on the project.

“Hunt and all parties involved with the construction of the project are working closely with OSHA and the local authorities during the ongoing investigation,” the contractor said in a statement.

OSHA investigators were called to the scene that evening. An OSHA spokesperson would not comment on the ongoing investigation but said that it had no record of past violations by Harrison Crane and Hoist. ENR could not reach representatives of the crane company for comment.

As the investigation unfolds, industry experts are raising questions about the possible cause. Photos taken at the scene show the tower laying across the building that was under construction. Two sections of the tower separated during the collapse. At the time of the collapse, the jib had already been removed from the tower crane, a Terex Peiner Model SK415, says a crane expert familiar with the accident, who asked not to be identified.

Investigators would likely focus on whether the tower sections were properly bolted at the time of the collapse, the source said.

“There are no obvious signs of damage at the bolt connections,” the source explained. “There should be damage to those connections or those areas would be bent, if the bolts were in there.”

A disassembly crane did not appear to be in use at the time of the accident, the source added. According to local press reports, a strong weather front rolled into the area on Saturday afternoon, creating gusts of up to 40 miles per hour.

Work on the 155,000-sq-ft building, which is scheduled to complete next year, was halted following the accident. Work is not expected to resume until after the completion of the OSHA investigation and removal of the damaged crane, according to a UT statement.

The accident is the second crane collapse in the state in recent weeks. A mobile crane fell over at a construction site in Conroe on June 28, killing the operator. Elsewhere, on July 5, a worker was killed when a crane collapsed at a project site on the Butte Des Morts Bridge in Winnebago County, Wisconsin.