More than 10,000 Afghan and U.S.-led coalition forces began a massive anti-Taliban operation across southern Afghanistan on Thursday, while a bomb killed seven people riding a bus to a coalition base for work.
Military forces are "moving forward with large-scale operations" in four southern provinces, Uruzgan, Helmand, Kandahar and Zabul, the U.S. military said in a statement. It is the largest offensive since the 2001 invasion that toppled the Taliban regime.
"It's a sign of the fact that the Taliban have never gone away," says CBS News chief foreign correspondent Lara Logan. "They were heavily defeated, but they stayed in the area, and they will always come back year after year."
As the offensive began, however, suspected militants continued their attacks.
A bomb hidden in a bus headed to a coalition base in southern Kandahar city exploded during morning rush hour, killing seven people and injuring 17, coalition officials and the Interior Ministry said. Afghan police initially said 10 people were killed.
Coalition spokesman Maj. Quentin Innis blamed the attack on Taliban militants and said it clearly targeted Afghans working for the coalition. Among the dead were interpreters and workers for the air base, Afghan officials said.
"It's the first time Afghans working here have been deliberately targeted by the Taliban. These are local guys trying to support their families," he said.
Bakery owner Amidullah said he was working in his shop when the explosion happened in front of him.
"When I came out of the shop, I saw the bus totally destroyed on the ground. I saw people dead and wounded lying on the ground," he said.
The military offensive, dubbed "Operation Mountain Thrust," is part of a major push to squeeze Taliban fighters responsible for a spate of ambushes and suicide attacks against coalition forces and Afghan authorities in recent months.
"This operation is as much a message to the Afghan people as it is to the Taliban," says Logan. "It's about the U.S. and the Afghan government telling the Afghan people, 'don't worry. We're still looking after you.'"
Afghans are concerned about the upcoming transfer this summer of command in the south from the U.S.-led coalition to the NATO-led International Security Assistance Force.
"People there are very, very worried about what that's going to mean. They feel the United States is abandoning them all over again," says Logan.
"There is no scheduled end date to Mountain Thrust. The coalition will continue operations well into the summer and until objectives are met," the statement said.
The offensive is focused on southern Uruzgan and northeastern Helmand provinces, where the military says most of the militant forces have gathered. Operations also will be conducted in the former Taliban stronghold of Kandahar and Zabul.
Troops on Wednesday built sand barriers and guard outposts around a small forward operating base in the Helmand district of Musa Qala, while others fired rounds from 119-millimeter howitzers deployed to the base's perimeter into the vast desert expanse.
"We do it so they know it's here and they know it could be pretty bad for them," said Lt. Col. Chris Toner, commanding officer at the base located 180 miles from the nearest permanent base in Kandahar. "This terrain up here favors the defender. I'm sure they know how many vehicles we have here, that we have artillery here, but that's OK — I know what they know."
Limited operations began May 15 with attacks on Taliban command and control and support networks. According to U.S. military and Afghan figures, about 550 people, mostly militants, have been killed since mid-May, along with at least nine coalition troops.
The operation will involve 2,300 U.S. conventional and special forces, 3,300 Britons, 2,200 Canadians, 3,500 Afghans and coalition air support, said Maj. Gen. Benjamin C. Freakley, U.S. operational commander in Afghanistan, who briefed The Associated Press on the offensive last week.
The operation is the largest launched since 2001. But U.S.-led troops have conducted large-scale operations elsewhere in Afghanistan involving several thousand soldiers, particularly in the east near the Pakistani border where Taliban forces routinely attack U.S.-led troops from towering mountain ranges.
On Wednesday, coalition and Afghan forces killed 26 suspected Taliban fighters in an attack on mountain positions in the eastern Paktika province, said provincial Gov. Akram Khelwak. Helicopter gunships and artillery fire supported ground troops and one Afghan police officer was wounded.
Three policemen were killed when they came under fire by Taliban forces late Wednesday night in southern Zabul province, according to provincial police chief Noor Mohammed. Two others were wounded during the hours-long gunbattle, he said.
In other violence Thursday, a mine exploded in southwestern Nimroz province along the main highway from Kandahar to Iran, killing two Turkish construction workers, said provincial spokesman Wahid Kharzad.