LAS VEGAS, Nev. -- Two workers are dead after 3,000-pound walls fell on them during construction of Project City Center, a $7 billion project on the Las Vegas Strip that will include luxury condos and a lavish hotel-casino.

Officials said the accident happened about 3:30 p.m. as the workers were attempting to install two steel retaining walls. The walls slipped, officials said, and fell on top of a group of men. Two of the men have been pronounced dead and two others were rushed to the hospital with serious injuries.

The identities of the victims have not been made public.

Project City Center is located at Las Vegas Boulevard and Harmon Avenue, south of the Bellagio hotel and casino. Tune in to FOX5News at Ten and FOX5Vegas.com for more on this developing story.