Search for woman thought to have fallen into sinkhole turns to recovery effort

Rescuers are likely to need an extra day of digging to find a missing woman who is believed to have fallen into a mine when a sinkhole opened in Pennsylvania, with police saying the search is likely to have now entered the recovery phase.

"Unless it's a miracle, most likely this is [a] recovery [effort]," Pennsylvania State Police Trooper Stephen Limani said.

Elizabeth Pollard, 64, was reported missing by family members after she went out to search for her cat on Monday night.

Officials believe she could have fallen into a 30-ft (9m) deep sinkhole connected to a mine in the town of Marguerite, that may have opened up below her as she was searching for her cat.

Speaking at a news conference Wednesday afternoon, Mr Limani said oxygen levels in the mine had lowered since they first started searching it.

"I know we have a lot of hopes, and maybe there is still a glimmer of hope, but based off of oxygen levels being a little lower, even though we've pumped oxygen into the mine, it's lower than what you would want for someone to try and sustain their life. It's been difficult," he said.

The two-day search operation for Mrs Pollard was hampered Wednesday as rescuers said the abandoned mine had become too dangerous to send people in to search underground.

"Because of the fragile state of the mine, we've had to change what we were trying to do," Mr Limani said.

"We were trying to basically suction the removal of dirt and debris and rocks, and even using water to try and soften the debris up or even push it out of our way to [now] where we have to dig out a massive area, more than four times the size of the area that we had originally done, to try and secure the mine so we can access it to try and go in there and recover her."

Cameras and electronic devices like microphones have been sent down into the mine, but rescuers have found no sign of Mrs Pollard so far.

Mr Limani said they had, however, spotted what appeared to be a shoe for a second time in the dirt and mud.

• What are sinkholes and what causes them?

In an interview earlier on Wednesday with CBS News, the BBC's US news partner, Mrs Pollard’s son, Axel Hayes, said he was going through a range of emotions.

“I’m upset that she hasn’t been found yet, and I’m really just worried about whether she’s still down there, where she is down there, or she went somewhere and found somewhere safer,” Mr Hayes said.

“Right now, I just hope she’s alive and well, that she’s going to make it, that my niece still has a grandmother, that I still have a mother that I can talk to.”

The family has been notified of the move to a recovery operation.

Mrs Pollard's car was found parked behind Monday's Union Restaurant in the town of Marguerite, 40 miles (65km) east of Pittsburgh, early Tuesday morning.

Her five-year-old granddaughter was inside, officials said, adding that the girl was cold but not hurt.

Officials believe that the sinkhole opened up as Mrs Pollard was standing on top of it while looking for her cat, named Pepper. They hope that she is sheltering in an underground "void".

"The sinkhole, it appears that it was most likely created during the time, unfortunately, that Mrs Pollard was walking around," Mr Limani said Tuesday.

"We don't see any evidence of any time where that hole would have been there prior to deciding to walk around and look for her cat."

At one point, more than 100 people were assisting in the rescue.

Temperatures, which have been below freezing the last several days, are much warmer inside the hole than they are at the surface.

Authorities had also not detected any dangerous gases that are sometimes found in abandoned mines.