Since the beginning of the year, more than 200 forest fires have taken place on the territory of Bulgaria. Natural fires that erupted because of lightning were just 2 percent. Seven percent of fires were proven to be intentional. 80 percent were caused by negligence and 14 percent erupted because of unknown reasons. "Guilt of perpetrators is difficult to prove as they must be caught while committing the crime. In most cases authorities rely on confessions from perpetrators," Vladimir Konstantinov, an expert from the Forestry Agency, told the Bulgarian National Radio in an interview. Currently, there are video surveillance systems, enabling prevention and rapid response to fires, but they cover about 15-20% of the forest areas of the country, the expert added. Each year some 22,000 decares of Bulgarian forests burn.