Two officials with Louisville's Downtown Development Corporation were seriously injured this morning when a staircase collapsed inside a historic building they were touring.Authorities say corporation director Alan Delisle, his deputy, Patty Clare (both pictured) and the building's owner fell about 30 feet. Delisle and Clare were both in serious condition at the University of Louisville Hospital Monday afternoon. The owner of the building, Paul Bariteau, was listed in fair condition. His wife, Carolan, was rescued from the building by firefighters and was not injured.Chris Poynter with the mayor's office says the officials were considering the vacant buiding at Eighth and Main Streets as a potential redevelopment project. "Over the last five years we've had no building code violations with this property. No issues with this property. The property owner has had a stellar record since he purchased this property many years ago," Poynter said.