A vast sinkhole has dramatically appeared in middle of an Illinois soccer pitch that was laid above a limestone mine, just days after amateur teams stopped using the grounds for practice. The collapse happened at Gordon Moore Park in Alton, Illinois, about 18 miles (30km) north of St Louis, Missouri, on Wednesday. The sinkhole appeared to be 100ft (30m) wide and 30ft (9m) deep. No injuries have been reported but all sports have been cancelled. “No one was on the field at the time and no one was hurt, and that’s the most important thing,” said Alton’s mayor, David Goins, in a post on Facebook. Mine operator New Frontier Materials said in a statement there was a “surface subsidence”, according to local news reports. The director of the Marquette Catholic high school athletic club, Brian Hoener, told the Alton Telegraph the effects of the collapse could have been “much worse”. “Last week at that time, we had 60 to 70 people out there on the field for our soccer camp,” he said. The Alton parks and recreation director, Michael Haynes, told NBC affiliate KSDK of St Louis that the collapse “looks like something out of a movie, right? It looks like a bomb went off.” Haynes said that Alton administrators were waiting to hear back from the mining company and to see “what the geologists and the engineers have to say about it”. “We’ll follow their lead on where to go from here,” Haynes added. “They can determine what happened, why it happened, how to prevent it and how we fix what has happened here.” According to studies, an increase in the occurrence of sinkholes is an “overlooked” aspect of climate change compared with other geo-hazards and typically mostly attributed to subsidence and groundwater pumping. The US Geological Survey also said sinkholes have been correlated to land-use practices, especially from groundwater pumping and from construction and development practices. A spokesman for New Frontier Materials said: “Safety is our top priority” and the company would “work with the city to remediate this issue as quickly and safely as possible to ensure minimal impact on the community”. The company said the collapse had been reported to the Mine Safety and Health Administration.