A huge sinkhole opened up on a football field in Alton's Gordon Moore Park, southern Illinois, swallowing a light pole, benches and artificial turf.The hole was caused by subsidence from nearby underground limestone mining and measures at least 100 feet wide (30.5m) and up to 50 feet deep (15m).The incident was captured on security video. No one was injuredSurrounding roads and the park are now closed, and the mining company reported the hole to the Mine Safety Health Administration.