PHILADELPHIA — The search for victims of a building collapse that killed six people wound down Thursday amid mounting questions about whether the demolition company that was tearing down the structure caused the tragedy by cutting corners.
The four-story building along Philadelphia’s busy Market Street collapsed Wednesday onto a Salvation Army thrift shop next door with a loud boom and a huge cloud of dust, trapping employees and others.
‘‘Buildings get demolished all the time in the city of Philadelphia with active buildings right next to them. . . . They’re done safely in this city all the time,’’ Mayor Michael Nutter said. ‘‘Something obviously went wrong here yesterday and possibly in the days leading up to it. That’s what the investigation is for.’’
Rescue efforts were buoyed early Thursday when a 61-year-old woman was pulled out alive and conscious after 13 hours under the rubble.
At least 12 others were hurt.