While an explosion in a minibus killed four civilians and injured eight in southern Afghanistan, a fierce gun-battle killed 25 factional fighters in Uruzgan province.

Aljazeera's correspondent in capital Kabul said the explosion in the bus occured just outside Laskhar Gah, the capital of Helmand province, about 55 km southwest of the capital.

The casualty figure was obtained from the provincial governor, Mullah Sher Muhammad.

Earlier reports had put the toll much higher at 17.

The explosion left a huge cracter on the ground. The bus was on its way from Marja district to Laskhar Gah.

Provincial officials immediately blamed the Taliban and al-Qaida  for the blast.

The twenty-five factional fighters are said to have died after fighting erupted early during the day between forces of a sacked provincial official and his successor.

A senioir Afghan official said the fighting was continuing and the authorities in Kabul were trying to broker peace.

Major attack

"In the past, they have staged small-scale attacks, but this one was the most serious of all"

Major Ghafar,
a senior Afghan security official

Reports coming in from the southeastern province of Khost quoted security officials as saying they killed 16 Taliban and al-Qaeda fighters while repulsing a major attack in which five of their own men were killed.

A senior Afghan security official labelled the Taliban attack as the biggest since their ouster from Kabul in December 2001.

"In the past, they have staged small-scale attacks, but this one was the most serious of all," Major Ghafar said.

Afghanistan’s rugged countryside in recent months has been witness to stepped up attacks by suspected Taliban and al-Qaida members.

A majority of the attacks are aimed at US-led forces in the country, while the rest target individuals and groups associated with the interim government in Kabul.

Two suspected al-Qaida members meanwhile have died in another explosion in Kabul.

Police said they were killed when a bomb they were reportedly preparing exploded.

“Two people were killed and one injured in a big explosion in the house,” said Abd al-Jamil Kohistani, director of Kabul Security Command Criminal Investigation department.

“The explosion totally destroyed the room they were in and made a hole down into the basement. That’s why we can say they were working on a big bomb,” the official said.