A Pentagon official, who asked not be identified, said the operation was at a very early stage, but he indicated that more troops would follow to pursue the war against Osama Bin Laden and his Taleban protectors.
A Taleban official responded by saying their forces were ready and would relish the opportunity to avenge the past 12 days of air raids.
Click here for a map of Afghanistan's battle lines
Air strikes on the Afghan capital, Kabul, and the city of Kandahar have continued during daylight hours on the Muslim day of prayer - in contrast to last Friday, when the United States said it was making no planned raids on Afghanistan.
Amid the continuing attacks, the Taleban's representative to Pakistan has returned from consultations with the Taleban leadership in Kandahar with what he says is a plan to resolve the crisis.
The ambassador, Abdul Salam Zaeef, gave no details, saying " I have brought a plan with me...I will discuss it with Pakistani officials and disclose it afterwards."
The Taleban have so far have refused to hand over Osama Bin Laden - a key demand by Washington.
In other developments:
US planes flying over Afghanistan have been broadcasting messages in local dialects warning people to stay off bridges and roads.
Mr Rumsfeld told a Pentagon briefing on Thursday evening that intelligence reports suggested that air raids in recent days had inflicted more damage than earlier attacks, leaving Bin Laden's forces vulnerable.
Taleban troops targeted
Bin Laden, is suspected of masterminding last month's terror attacks on New York and Washington that left more than 5,000 people dead.
At least six civilians - including five members of one family - were killed in the capital Kabul during bombing on Thursday.
A senior Taleban spokesman, Abdul Hai
Mutmaen, said on Thursday that between 600 and 900 people had been killed or were missing as a result of 12 days of US-led strikes on Afghanistan. The US admits some bombs have gone astray but says the Taleban's figure is far too high.
Aid agencies' appeal
For the first time, Mr Rumsfeld has spoken of helping to arm the Northern Alliance.
"They're going to have some help in food, they're going to have some help in ammunition, they're going to have some help in air support and assistance," he said.
A group of six international aid agencies has called for a pause in the air strikes to allow food supplies to be delivered before Afghanistan's severe winter sets in.
"We have seen some movement of what we believe to be the al-Qaeda forces - and they have been specifically targeted while they were moving," Mr Rumsfeld said.
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Click here for a detailed map of the strikes so far |
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