ELSENBORN, Belgium — The wildfires burning across Europe this summer have exposed a potentially deadly threat lurking beneath the blackened landscape: rusty bombs and mines from World War I and II that threaten crews responding to the flames. Some of the weapons have exploded in the intense heat. Blasts have been reported in France, Belgium, Germany and the Netherlands, where a bomb-disposal team was dispatched to check a forest threatened by flames near a site of fierce fighting in the Limburg province in 1944. …This wildfire season was supercharged by heavy rains in January that spurred vegetation growth, which became kindling when the summer heat arrived. Those temperatures, combined with drought conditions, low humidity and stiff winds, offered an ideal environment for fire. …Unexploded ordnance is even more dangerous around wildfires because heat can trigger the explosives, said Jonas Tepe, a spokesperson for North Rhine-Westphalia, just across the border in Germany.