Hundreds of firefighters were battling wildfires in eastern Germany and neighboring Czechia on Tuesday as tourist regions and residential areas were being evacuated. A large wildfire was spreading quickly in the eastern German state of Brandenburg in a region with lots of bone-dry pine forests where firefighters have to be especially careful because of old World War II ammunition that’s still buried there, German news agency dpa reported. The large fire in the Elbe-Elster district has already destroyed an area of about 850 hectares and continued to spread quickly because of gusty winds blowing from changing directions. Seven firefighters were injured, four of whom had to be treated in a hospital for smoke inhalation. No residents were injured, but a pig breeding farm burned down and several animals died. The state’s explosive ordnance disposal service has designated a small area near the village of Rehfeld as a site where old ammunition could be buried, deputy forest fire protection officer Philipp Haase told dpa. Two German military firefighting helicopters were on site trying to extinguish the flames from the air because firefighters were not allowed to access the area for fear that the ammunition could explode. Authorities said it was not clear when the fire could be brought under control. More than 350 firefighters were battling the flames and around 300 people from various villages had to be evacuated. “The situation is still serious. We still have pockets of fire,” local district fire chief Steffen Ludewig told dpa. Read: Governor declares emergency over wildfire near Yosemite Further southeast, firefighters from several countries have joined forces to battle a fire in a national park in northern Czech Republic that has spread to the state of Saxony in neighboring Germany. The fire in the Bohemian Switzerland park broke out on Sunday and was mostly contained before windy weather caused it to spread again on Monday afternoon and overnight. Firefighters said some 30 hectares have been affected in the park and more across the border in Germany. No injuries have been reported. Some 80 people have been evacuated from the border town of Hrensko, and more from the village of Mezna, where the flames have destroyed or damaged several homes, firefighters spokesman Lukas Marvan said. Dozens of German children were evacuated from a summer camp on the Czech side of the border and transported back to Germany. Czech Prime Minister Petr Fiala and Interior Minister Vit Rakusan were visiting the area on Tuesday. Rakusan said some 400 firefighters have been in action and the blaze was not under control by midday Tuesday. "The situation is very serious,” Rakusan said adding that several neighboring countries had responded to the Czech Republic's call for help to extinguish the fire. Poland and Slovakia said they were sending helicopters while Italy offered special Canadair planes designed for firefighting. The German military announced it would send four helicopters to the border region to help fight the flames, dpa reported.   The Czech Hydrometeorological Institute said the smoke has spread 100 or more kilometers (60 miles or more) from the fire.