The attack early on Sunday happened on the Uruzgan-Kandahar highway near a village in southern Kandahar, where a day earlier four Canadian soldiers were killed in a suspected Taliban roadside bombing.
A group of heavily armed insurgents launched a two-hour attack against the headquarters of the Thavazoo company in the Shah Wali Kot district, said Haji Mohammed Yussef, the company's director.
One guard was killed in the attack and two were wounded before the remaining security personnel fled, Yussef said.
The Taliban fighters then entered the compound, burnt 14 trucks and bulldozers and stole equipment before escaping.
Yussef said coalition forces gave him a contract to build a 40-km stretch of road, 25km of which had been completed.
Insurgents have been stepping up attacks against coalition and Afghan forces, looking to reinstate the Taliban government which was toppled by US forces four years ago for harbouring Saudi-born Osama bin Laden and his al-Qaeda group that claimed the September 11, 2001 attacks on the United States.
US and Afghan soldiers also arrested 16 Taliban in two raids on Saturday in the southern Zabul province near Kandahar, an Afghan general said.
General Rahmattalluh Rufi said: "The Americans are questioning them now to see if they are important Taliban members or not."
It was unclear if Sunday's Taliban raid and the arrests were linked to Saturday's killing of four Canadian soldiers, the deadliest attack on that nation's troops since they were deployed in 2002.
The Taliban killed six Canadian
troops on Saturday
Canadian officers said Taliban insurgents detonated a massive roadside bomb that destroyed one of four armoured vehicles in a convoy in Gomboth, a village about 40km north of Kandahar and a former Taliban stronghold.
After the blast, insurgents exchanged fire with soldiers before fleeing.
At least 16 Canadians have been killed since February 2002, when a 2,200-strong Canadian contingent moved into southern Afghanistan to relieve US troops.
Rising violence is a growing concern for nations contributing troops to a force operating under a Nato mandate.
The Nato force is to be increased from its current 10,000 soldiers to about 21,000 by next November as it gradually assumes command of all foreign troops in Afghanistan.