Fire has broken out afresh in Aberdare National Forest three days after another blaze was put out.
The raging flames have so far consumed 500 more hectares, the Kenya Forest Service (KFS) said.
KFS Nyeri Zonal Manager Muchiri Mathinji on Wednesday said the fire restarted from stumps that were still smouldering from the flames that broke out on Friday last week.
“We are still trying to fight the fire that is fast spreading to the northwest of the forest within the moorlands,” said Mr Mathinji.
Some 50 people have been mobilised to battle the blaze in a joint effort by the KFS, Kenya Wildlife Service and Community Forest Association.
“As of now, the fire poses no danger to the indigenous forest. We are making sure that we prevent the fire from touching the main forest,” he said.
So far, the fire has only consumed the shrub moorland grass and heaths, which Mr Mathinji said can regenerate rapidly upon the onset of the long rains.
The fire has consumed 6,500 hectares of the forest in six days.
Mr Mathinji said rugged terrain and strong winds blowing towards the northwest in Nyandarua County were giving the firefighters a hard time.
“The terrain is hilly and it is taking us time to fight the fire. It is a kilometre's walking distance but by the time we get there, the fire will have already spread and the firefighters already tired,” he said.
Officers from the two wildlife agencies are criss-crossing the forest to assess the damage using vehicles.
“We are still investigating the actual cause of the fire,” said Mr Mathinji.