Two US soldiers and seven Afghan policemen were killed in separate explosions yesterday, highlighting the level of violence faced by Marines pressing one of the biggest assaults in eight years.
In another incident, one security guard died and four others were wounded when a suicide bomber detonated an explosives-packed vehicle near a private security company's four-vehicle convoy in Gereshk district, Daud Ahmadi, a spokesman for the Helmand provincial administration said.
Nearly 4,000 marines and 600 Afghan forces last Thursday launched a massive operation in Taliban strongholds in the south, in a pivotal test for the new strategy and to protect the local population ahead of the polls on August 20.
US President Barack Obama has put Afghanistan at the heart of his foreign policy, determined to stabilise the war-torn country and dispatching thousands of extra American troops in the run-up to landmark elections next month.
But bomb attacks and clashes in the south and elsewhere yesterday emphasised the scale of a Taliban insurgency that is at its deadliest since the 2001 US-led invasion ousted the extremist regime.
Seven police officers and two army soldiers were killed in bomb blasts in the southern flashpoint provinces of Kandahar and Helmand, where the US Marine offensive is underway, the defence and interior ministries said.
"A roadside bomb struck a police vehicle which resulted in the martyrdom of seven policemen," the interior ministry said. Two other police were wounded.
The defence ministry said the two Afghan soldiers were killed last Friday in Helmand's Musa Qala district, a former Taliban stronghold, in perhaps a worrying sign that despite military offensives insurgents were regrouping.
The government departments blamed both bomb blasts on insurgents and the enemies of Afghanistan, a phrase used to refer to the Taliban.
In the north, another bomb blast killed an Afghan civilian and wounded another in the province of Jawzjan, the ministry said.
In eastern Afghanistan, two US soldiers and at least 22 suspected militants died in fighting.
"There was an explosion, a possible IED (improvised explosive device), in Paktika province this morning in which two US service members were killed," said military spokesman Sergeant Charles Marsh.
The military base then came under insurgent fire and air support was called in against the rebels, Marsh said.
The troopers were operating under NATO, the alliance force said later, adding that at least 10 militants were also killed in counter-attack involving air support.
The interior ministry in Kabul put the insurgents' death toll at 22 while a local spokesman for the Paktika administration gave a toll of 32. None of the tolls could be independently verified.
"Insurgents attacked with indirect fire, including multiple rockets and mortars, at least one of which contained white phosphorous, small-arms fire and a vehicle-borne improvised explosive device," the force said in a statement.
Hamidullah Zhwak, the Paktika provincial administration spokesman said the US casualties were caused when Taliban insurgents blew up a fuel tanker in front of a local government building in the district of Zirok.
"After the blast, American helicopters came in and attacked the Taliban, who were preparing to attack the district headquarters," he said.
The Taliban later claimed responsibility for what it described as a two-pronged attack in which five militants died, excluding a suicide bomber.
"Today Hafiz Omar carried out a suicide attack with 8,000 kilos of explosives in a (fuel) tanker on an American base... in Zirok," Taliban spokesman Zabihullah Mujahed told AFP.
"At the same time 100 mujahedeen (holy fighters) attacked the base just after the explosion... Americans suffered heavy casualties and we lost five of our fighters," the spokesman said.
US commanders have said they would try to persuade locals that the Afghan security forces - backed by Western troops - offered them a better long-term future than the fundamentalist Taliban militia.