Digging crews resumed work early Thursday in the effort to locate a woman who authorities fear died after falling into a sinkhole above an abandoned Pennsylvania coal mine.

Fewer than a dozen searchers, including state police and excavator operators, have returned to the spot where 64-year-old Elizabeth Pollard is thought to have plummeted through a freshly opened sinkhole about three days ago.

Authorities said late Wednesday they no longer think they will find Pollard alive. She was last seen Monday evening, searching for her lost cat, Pepper. Her car was discovered some 10 hours later, not far from her house in the village of Marguerite, with her 5-year-old granddaughter inside, unharmed.

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Family Holds Out Hope Amid Grim Outlook

Axel Hayes, Pollard’s son, was at her house about half a mile (0.8 kilometers) from the sinkhole on Thursday with his father, Kenneth Pollard, still hoping the search will produce good news while bracing for the worst.

“We’re just trying to hold hopes out,” Hayes said in a phone interview. “We’re not really sure what to feel right now.”

After overnight snowfall left a thin coating on the ground, work crews were maneuvering a bulldozer and crane near the sinkhole. State police on the scene said an update on the search might be provided later in the day.

Pennsylvania State Police spokesperson Trooper Steve Limani told reporters late Wednesday that work would not continue overnight, as they had seen no signs of life or any other reason to press the dig in ways that could risk harm to rescuers.

Hayes said he understood the decision: “I’d rather not anybody else get hurt.”

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Challenging Conditions Hamper Search Efforts

The hole is located by Monday’s Union Restaurant in Marguerite, a Westmoreland County community some 40 miles (65 kilometers) east of Pittsburgh. Pollard’s vehicle was found about 20 feet (6 meters) from the sinkhole, which authorities believe may have opened just as Pollard walked over an area of mine subsidence.

Efforts to find her have been frustrated by treacherous conditions for search crews inside the mine, including water and sticky mud, wooden supports that have been in place since the mine was last in operation some 70 years ago, and areas where the roof has caved in.