Examples of both intermediate and long term fallout occurred after the Chernobyl accident. Chernobyl was a nuclear power facility in the Soviet Union. In 1986 it accidentally contaminated over about 5 million acres () in Ukraine. The main fuel of the reactor was uranium, and surrounding this was graphite, both of which were vaporized by the hydrogen explosion that destroyed the reactor and breached its containment. An estimated 31 people died within a few weeks after this happened, including two plant workers killed at the scene. Although residents were evacuated within 36 hours, people started to complain of vomiting, migraines and other major signs of radiation sickness. The officials of Ukraine had to close off an 18-mile area. Long term effects included at least 6,000 cases of thyroid cancer, mainly among children. Fallout spread throughout Western Europe, with Northern Scandinavia receiving a heavy dose, contaminating reindeer herds in Lapland, and salad greens becoming almost unavailable in France.