(CNN) -- A new round of attacks on Afghanistan began Monday with strikes near at least two cities, and the United States said its anti-terrorist campaign could lead it to attack other nations, as well.
In Kandahar, the Taliban's stronghold in southern Afghanistan, power went out and witnesses said explosions and anti-aircraft fire could be heard nearby. In Kabul, power was out and Afghanistan's Radio Shariat went off the air.
"We are hitting targets similar to those hit yesterday," said Gen. Richard Myers, chairman of the Joint Chiefs of Staff.
Sources in Kandahar told CNN that Taliban officials had decided not to take on the overwhelming allied force directly, but will battle the allied effort as a guerrilla war.
The United States says it has clear evidence that the suspected terrorist leader Osama bin Laden's al Qaeda organization was responsible for the September 11 attacks on New York and Washington. The Taliban refused repeated U.S. demands to surrender bin Laden before airstrikes began Sunday.
Strikes resumed as U.S. officials notified the United Nations that its anti-terrorism campaign could involve strikes on other countries beyond Afghanistan. And Defense Secretary Donald Rumsfeld warned the U.S. war on terrorism could last years.
Myers said the United States and Britain hit 31 targets on Sunday. No U.S. aircraft have been lost, Rumsfeld said.
Myers said "we have to assume" that some of the anti-aircraft missiles fired at U.S. planes were U.S.-built Stinger missiles supplied to Afghanistan during the Soviet occupation in the 1980s.