The US military said on Saturday the bombardment took place in rough terrain about 230km south of Kabul in Paktika province.
It was the second time this week the 20,000-strong US-led occupation forces have called in an air strike in southern Afghanistan.
On Tuesday, US aircraft bombed an area between Qalat in Zabul province and Spin Boldak on Afghanistan's southern border after a patrol came under fire.
Local officials said 20 suspected Taliban were killed by the bombing or by Afghan soldiers on the ground in Arghistan, a town which lies roughly mid-way between Qalat and Spin Boldak.
The Taliban has regrouped after
being ousted from power in 2001
But the United States has only confirmed the deaths of two fighters in the incident.
The bombardment came after two American troops were wounded in a firefight on Thursday night near the town of Shkin in the border region.
US military spokesman Lieutenant Colonel Tucker Mansager said: "We had two coalition casualties in the engagement that led up to us using ordnance down there."
Local officials have said as many as 200 suspected Taliban fighters armed with rocket-propelled grenades and AK-47 rifles are hiding out in the mountains bordering Pakistan.
US-led forces are concentrated in the south and southeast of the country, particularly along the porous border area believed to harbour al-Qaida fighters and as well as Taliban members.
The Taliban government was ousted from power in 2001 by a US-led coalition.
In another incident in the southeast, US soldiers allegedly killed one man and arrested a second in a house in Khost city, a local official said.
"They entered the house midnight on Friday and shot dead the owner of the house (who was) sleeping outdoors, close to the main gate," Khost province's security director Muhammad Zaman said.
US forces in Afghanistan are
hunting Usama bin Ladin
"Right at this moment I don't have information on whether these people were terrorists and Taliban," he added.
A spokesperson for the occupation forces was not immediately available for comment.
In the lead-up to presidential and parliamentary elections scheduled for September, Afghanistan has been hit by a wave of violence directed against US and Afghan troops and aid workers in the south and southeast.
The US military announced on Saturday that thousands of Afghan national army troops would be deployed around the country to provide security for voter registration and the polls.