A tall column of smoke is clearly visible Thursday morning on Vitosha Mountain from Bulgarian capital Sofia, which lies on the mountain's outskirts.

The smoke comes from a wildfire that erupted Tuesday around noon in the Mecha Polyana (Bear's Glade) locality between the Aleko sports center and the Bistrishko Branishte reserve.

The wildfire burned some 25 acres of alpine grasslands and pine forests, intially fanned by strong winds Tuesday.

It was tackled by scores of firefighters, foresters and volunteers who had to work on the ground in the difficult terrain.

They said they fear the fire might spread to the nearby Platoto locality and the Torfeno Branishte reserve, which would be dangerous, as it contains vast amounts of peat.

Thursday morning Sofia mayor Yordanka Fandakova and representatives of the fire service had stated that the wildfire is completely under control.

But the smoke pillar rising from the area, as seen from down in Sofia, has significantly grown in size since early morning.

Last Thursday firefighters managed to quench a similar wildfire that erupted in the nearby area of Vitoshko Lale ski runway.

In early July, a large wildfire in a difficult area of the Bistrishko Branishte reserve took the efforts of hundreds of firefighters, foresters and volunteers to extinguish for no less than seven days.

The July wildfire coincided with largescale protests against amendments to Bulgaria's Forestry Act, which citizens said were tailored to benefit investors such as the Vitosha Ski company, which had announced intentions to expand activities in areas of protected nature.