A giant sinkhole that opened in a southern Illinois soccer field swallowed a large light pole and left a gaping chasm above an area where limestone is mined underground, authorities said. No injuries were reported after the sinkhole opened Wednesday morning in an artificial turf soccer field at Alton’s Gordon Moore Park. Security video that captured the hole's sudden formation shows a soccer field light pole disappearing into the ground along with benches and artificial turf. The hole is estimated to be at least 100 feet (30.5 meters) wide and 30 feet (9.1 meters) to 50 feet (15.2 meters) deep, said Michael Haynes, director of the Alton Parks and Recreation Department. Gordon Moore Park and roads around it are now closed indefinitely in the southwestern Illinois city located about 25 miles (40 kilometers) north of St. Louis along the Mississippi River. New Frontier Materials Bluff City, which operates a limestone mining in the area, said the sinkhole resulted from “surface subsidence” at its underground mine in Alton. The collapse was reported to the Mine Safety Health Administration in accordance with applicable regulations, New Frontier Materials spokesman Matt Barkett said in a statement. “The impacted area has been secured and will remain off limits for the foreseeable future while inspectors and experts examine the mine and conduct repairs," he said. “... We will work with the city to remediate this issue as quickly and safely as possible to ensure minimal impact on the community.” Haynes said that mines have been in operation in the area for several decades.