ATHENS, Aug 3 (Reuters) - Awildfire raged uncontrolled north of Athens on Tuesday, burning homes and forcing authorities to order more evacuations as they grappled with 81 forest fires during Greece"s worst heatwave in over 30 years. As night fell, more than 500 firefighters battled the blaze on the lower slopes of Mount Parnitha, assisted by nine helicopters, seven aircraft and 305 police in a densely vegetated area in the suburbs of Varympopi and Adames. "It is a difficult day for the country, we had 81 forest fires in the last 24 hours due to the extreme weather conditions," Deputy Civil Protection Minister Nikos Hardalias told reporters. Temperatures of more than 40 Celsius (104 Fahrenheit) and winds have fanned wildfires in different areas of Greece in recent days. On Tuesday, some places recorded temperatures of over 46 Celsius (115 Fahrenheit). The blaze north of Athens had three main fronts at the towns of Varympopi, Adames and Thrakomakedones, scorching homes and cars and forcing residents to flee. "We will continue our fight through the night, our priority is to save lives," the minister said. Authorities had removed valuables at the former royal estate at Tatoi nearby and the civil protection service ordered residents of the Olympic Village to leave their homes. They could stay at designated hotels at the state"s expense. Seven people were taken to hospital with breathing problems. Earlier,children were evacuated from a summer camp and residents were ordered out of their homes in the suburbs of Varympopi, Adames and Thrakomakedones, some 20 km north of central Athens. Some stayed on to defend their houses with garden hoses. Explosions sounded as the wildfire engulfed an unknown number of homes. Equestrian clubs let horses loose to flee the fire. Prime Minister Kyriakos Mitsotakis visited a fire brigade operations centre coordinating efforts to contain the blaze and other fires, in the Peloponnese Peninsula and on the islands of Evia and Kos. "All available means and resources have been deployed in the fight on multiple fronts," his office said in a statement. "In these difficult times, the priority is to protect human lives." In Athens, the power grid operator IPTO said the fire had damaged parts of the grid, posing a major risk to the electricity supply in parts of the metropolitan region. "Dozens of homes are being burnt," Michalis Vrettos, deputy mayor of the Acharnes region, told Open TV as thick plumes of smoke rose over the houses behind him. The fire disrupted train services and forced authorities to seal off part of a national motorway. Europe is grappling with a summer of extreme weather, from heavy flooding in the north to the severe heatwaves and fires that have engulfed several areas in the Mediterranean region. Greece"s neighbour, Turkey, was fighting wildfires near some of its most popular tourist resorts for a seventh consecutive day on Tuesday. read more