The already-risky work of fire crews battling a wildfire in England's North York Moors National Park has been made all the more dangerous by World War II-era bombs and tank shells hidden under the dense, dry vegetation.

A local fire official said Wednesday that there had been nearly 20 explosions as the fire burns through brush to detonate the hidden weapons.

The Langdale Moor fire, which started on August 11, has charred about 10 square miles in the picturesque coastal region of North Yorkshire. Emergency fire crews have been tackling the blaze, aided by local farmers and game keepers who've swung into action with water tanks and tractors, dousing brush and helping cut fire breaks through the moorland, which is covered largely by dense shrubs and grass.

Dyson said part of the active fire area was a tank training ground during the 1940s, explaining why so many weapons were still lurking under the first layers of the rugged landscape. 

There is still a U.K. military site, the RAF Fylingdales radar station, in the immediate area. Britain's Ministry of Defense in London said an explosive ordnance disposal team had found "various World War II-era unexploded ordnance items," declaring them to be "inert practice projectiles."

https://www.cbsnews.com/amp/news/langdale-moor-fire-map-wildfire-uk-yorkshire-whitby-wwii-bombs-shells-explosions