A park in Alton, Illinois, remains closed with no timetable to reopen, more than 10 days after a giant sinkhole opened up in the middle of a soccer field.Footage captured by 618 Drone Service on July 6 shows the progression of the sinkhole.The sinkhole, formed at Gordon Moore Park on June 26, was the result of a mine collapsing, park officials said.Nobody was on the field at the time of the collapse, Alton mayor David Goins told local media.The park remained closed and mining operations were halted, pending an ongoing investigation into the cause led by the Mine Safety Health Administration (MSHA), city officials said in a statement on July 5.