"The fires have gutted forests inside the national park and those managed by state forestry company Perhutani," Sri Puryono, the head of the Central Java provincial forestry office, said here recently.
The affected forests include those in Mount Lawu, Sumbing, and Guci.
Material losses inflicted by the fires are estimated to reach about Rp800 million.
"The value is relatively small, but the real loss concerns the ecology due to the forest damage," he said.
One of the main causes of the fires were related to the human factor, he said.
The prolonged drought had also triggered the fires. Most of the fires occurred in locations which were difficult to reach, he stated.
The forestry office and Perhutani will soon deploy a team supported by military and police personnel to extinguish the fires.
Forest fire hot spots have been detected in around 10 provinces in Indonesia during the present dry season which has also triggered water crisis especially on Java Island.
The forestry ministry`s data obtained from NOAA Satellite 18, showed that there were 22,120 hot spots throughout Indonesia from January to September 12, 2011.
The hot spots have been found among others in West Kalimantan (4,105 hot spots), Riau (3,208), South Sumatra (3,340), Central Kalimantan (2,778), Jambi (1,305), and North Sumatra (795).
Last year, there were a total of 9,880 hot spots in Indonesia, including 1,785 hot spots in West Kalimantan, 1,707 in Riau, 1,481 in South Sumatra, 831 Central Kalimantan, 603 in Jambi, and 530 in North Sumatra.
In dry season, which usually begins in July until October, some parts of Indonesia are prone to forest and peatlands fires.