PHILADELPHIA (CBS) –- A day after a deadly building collapse in Center City, the mayor’s office has identified the six victims who were killed and 13 of the injured. The investigation into what caused the collapse is ongoing.

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The search for survivors ended at about 3 p.m. after going through the night Wednesday and into Thursday. (See Related Story)

VIEW: Photos From The Scene

The collapse took place at about 10:30 a.m. Wednesday in a pair of low-rise buildings at 22nd and Market Streets, one of which was under demolition at the time (See Related Story).

Authorities said when the building under construction collapsed, it sent debris through the wall and roof of the adjacent one-story Thrift Store that was fully operational at the time, nearly flattening it.

Eyewitnesses recalled hearing a loud rumbling sound before the collapse.

During a news conference Thursday morning, Mayor Michael Nutter said approximately 75-percent of the collapse site had been searched and 42 emergency personnel had remained on the scene. The remaining 25-percent was completed by 3 p.m. Thursday.

“Today, we mourn the loss of six Philadelphians who perished in the terrible tragedy at 22nd and Market streets on Wednesday. Our deepest condolences go out to the families and friends of the deceased,” said Mayor Michael A. Nutter. “I ask all Philadelphians to remember those who perished and their families in their prayers and thoughts.”

Nutter identified the deceased as: Kimberly Finnegan, Borbor Davis, Juanita Harmin, Mary Simpson, Anne Bryan and Roseline Conteh (Read: About The Victims).

The following individuals were among those injured in the collapse: Susan Randall, Betty Brown, Shirley Ball, Linda Bell, Jennifer Reynolds, Nadine White, Margarita Agosta, Richard Stasiorowski, Rosemary Kreutzberg, Rodney Geddis, Felicia Hill, Daniel Johnson and Myra Plekan.

Mayor Nutter praised the rapid response and prolonged effort of the city’s first responders as well as those citizens who selflessly entered the demolition site in the minutes after the collapse to help in the search for survivors. “Reports yesterday identified a number of individuals who took quick action, including Jordan McLauglin, Ray Kauffman, Bill Roam, Patrick Glynn and Brian Mullins. On behalf of the City, I want to thank them for their quick thinking and courage,” Mayor Nutter said.

LISTEN: City Officials Hold Day-After Press Conference (runs 18:22) …

Following the collapse, three people, including two women, were taken to Hahnemann University Hospital. Five people were taken to Thomas Jefferson University Hospital, and five were taken to the Hospital of the University of Pennsylvania. Three of the victims that were taken to HUP were released Thursday.

One of those taken to the hospital was a 66-year-old woman who was pulled a live from the rubble at about 1 p.m., more than two hours after the initial collapse. The victim, officials, say, walked away from the scene after being rescued from underneath the rubble.

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An hour later, rescuers recovered the body of a 35-year-old woman found inside the Salvation Army Thrift Store.

Just before 8 p.m., rescuers recovered the body of a second victim. At about 8:15 p.m., rescue crews pulled the body of a third victim from the rubble, and a fourth victim was recovered about two hours later.

Sixty-one-year-old Myra Plekam, of Kensington, was pulled alive from the rubble at about 11:45 p.m. Wednesday night. She was taken to the Hospital of the University of Pennsylvania where she is listed in critical condition.

At a news conference late Wednesday night, Mayor Michael Nutter confirmed six people — five women and one man — were killed in the building collapse. All six were found inside the thrift store.

“This has been a tough day here in the city of Philadelphia. But we’re a tough city and we’re quite resilient and our efforts will not stop,” said Nutter.

About The Building …

Nutter said that a citizen complaint was filed in May about the property at 2134 Market Street. The property that collapsed was located at 2136. Nutter said the property at 2134 Market was inspected and nothing unsafe was found.

However, it was revealed during the Thursday news conference that the city’s Licenses and Inspections Department didn’t inspect the demolition site after work began.

Nutter said that buildings get demolished in Philadelphia with active buildings next to them, but that “something obviously went wrong here.”

Philadelphia DA Seth Williams issued a statement today indicating that a criminal investigation will be conducted.

“It is premature to assign criminal responsibility,” his statement said in part, “but at the appropriate time we will conduct a thorough review of all the facts and evidence that resulted in such a tragic loss of life.”

Although the cause of the crash is under investigation, the city’s Department of Licenses and Inspections said the demolition company had proper permits for the work.

Street Closures …

Thursday 21st and 23rd Streets, Market to Arch Streets and 22nd Street between Chestnut and Arch remain closed.

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