KABUL: Take a few grams of explosive, the remnants of a US cluster bomb or a rocket, add some wiring and you have the ingredients for the terror campaign being waged by militants against the Afghan government as the country prepares for elections.

Militants from Afghanistan's hard line Taliban regime, ousted in 2001 by a US-led offensive have swapped broader offensives using AK-47s and rusty rockets for home-made bombs in a low-tech guerrilla campaign aimed at derailing the country's first presidential polls on October 9.

In the past week, militants have staged two bomb attacks in the country's biggest cities, sowing terror in the capital Kabul on Sunday with a car-bomb that hit a US security firm killing three of its US staff and at least three others.

The latest bomb attack in southern Kandahar city on Friday followed a similar pattern. A remote-controlled detonator attached to a car exploded, narrowly missing a United Nations vehicle but killing one Afghan man and wounding five other people.

"There is certainly a change in their tactics," said Nick Downie, a military expert who provides security information for aid organizations in the country. The Taliban and other anti-government militants are using "classic terrorist-type tactics," similar to those used in Northern Ireland in the 1980s and early 1990s.

"Improvised explosive devices are certainly something which is highly effective as we have seen on a number of occasions," he said. Since the Taliban were toppled in 2001, they have retreated to strongholds in the south and southeast of the country and have taken to harassing US-led forces, UN staffers and electoral workers with home-made bombs.

While still engaging in brief gun-fights with US and Afghan troops in the southeast, militants have targeted the capital Kabul and other cities with improvised bombs.

"To place a bomb or an explosive device on a road or in a crowded place even inside the cities is much easier for Taliban than to fight face-to-face with troops," said General Abdul Wasay, military spokesman for south.

Wasay said the Taliban had changed their tactics in recent months to avoid confronting US troops and the 12,000 strong fledgling Afghan army. The US-led coalition has 18,500 heavily armed troops mostly hunting militants in the south and there are close to 8,000 Nato-led peacekeepers patrolling Kabul and quieter northern provinces.

Guerrilla tactics are the only way the militants, who are not strong enough to topple US-backed President Hamid Karzai's government, can sow terror, said an Afghan official and military expert.

"These kind of bombs are the only weapon that they can use to impact casualties on coalition and government troops," said the expert. Downie said the Taliban appeared to have fragmented, and have scaled back major offensives.

"Last year we saw the emergence of some large numbers of Taliban fighters but this year we have seen the emergence of smaller groups," Downie says. The US military admits fighters have shifted their tactics to home-made bombs but attributes this to the weakness of their enemies.

"The tactics of the Taliban may be changing because their attacks on coalition forces have been ineffective," Major Scott Nelson said. "Therefore they have changed their tactics to target softer targets like NGO, Afghan civilians and members of the international community to terrorize and force those who aid Afghanistan," he added.

Bomb attacks have seen a spike with 10 improvised explosive attacks against US troops, the government and international workers here in August, and five attacks in July, Nelson said.

Since May more than 10 US-led soldiers have died in violence, most of them hit by improvised bombs, either buried on a road or placed in a vehicle abandoned by the roadside.

However, Nelson said intelligence was improving and an "untold number" of lives had been saved as the Afghan people were reporting the location of bomb devices to US troops and the government.

Improvised explosive devices "are a threat because they are indiscriminate, much as mines," said Nelson adding the US military was learning to cope with the new tactics. After 25 years of war, Afghanistan is awash with explosives and weapons caches making constructing home-made bombs a simple task for militants and the devices are effective.

Ironically, some of the cluster bombs dropped in the 2001 US air campaign in Afghanistan are now being remodelled by the Taliban to use against US troops. "You reap what you have sown," Downie said of cluster bombs fragments which are now used in anti-American home-made bombs. -AFP