Cricket players were forced to flee after they were surrounded by a swarm of bees.
One of the players was stung during the under-15s cricket match at Elvaston in Derbyshire.
Officials had to call off the match between South Derbyshire and Derby City on Wednesday.
Elvaston Cricket Club chairman Terry Gorman said: "It was one of the most amazing sights I have ever seen."
The bees interrupted the match after the first few overs - forcing the players to take cover in the pavilion.
They waited for an hour but after returning to the pitch, the bees swarmed around them again and the match was abandoned.
Mr Gorman added: "We called the players off and the umpire said it was unsafe to continue.
"None of us had seen bees that were that aggressive. Even the experts are struggling to explain it to us."
Steve Stubbings, Derby under 15s coach and former Derbyshire County Cricket Club captain, said: "I have never seen anything like it before - a constant stream of bees flying across the ground.
"The swarm at the end was enough to send me packing."
South Derbyshire District Council's environmental health team is monitoring the bee problem, but have not yet discovered why the swarming took place.