Dirk Bischof, 46, was in the park with his daughter when he saw the air ambulance land.
He said: “The actual incident happened inside the festival ground. We already went like three times this week so we were just chilling in the park.
“In typical south London style, the people were standing around, spectating.
“I've spoken to quite a few people to find out more and many told me "it was a miracle nothing happened sooner, considering it was school holidays'.
“Burgess Park, being so close to the various estates has often got an explosive atmosphere during school holidays, with lots of young people descending onto facilities."Nothing to see here, move along....