A forest fire has broken out in the radioactively contaminated exclusion zone around the Chernobyl nuclear power plant in Ukraine, officials said on Wednesday. An area of around 20 hectares is on fire, the governor of the Kiev region, Ruslan Kravchenko, said on Facebook. However, background radiation levels were within the norm, he added. More than 200 firefighters, including 50 soldiers, have been deployed to battle the flames, according to the administration of the restricted zone. They have already succeeded in containing the fire, it said. The cause of the fire was initially unclear, but t…