The NATO base in Afghanistan's Helmand province was attacked recently by militants, four of whom died in the attack. Also, local authorities in Helmand said several Afghan civilians were killed or injured Monday in a roadside bomb blast in Marjah district.
Karzai said it's the presence of foreign military forces that is leading to the attacks and demanded that Kabul control military units formed by NATO in Afghanistan, the Voice of Russia reported Thursday.
Helmand district chief Fahim Mosazai said the bombing incident occurred this week at Shor Shorak area, killing at least four civilians and injuring six others, after a civilian vehicle hit an IED planted by militants.
The Taliban claimed responsibility for the attack.
Helmand, long one of Afghanistan's most restive provinces, has been garrisoned by British military forces deployed by the International Security Assistance Force since 2006.
Helmand's town center is Sangin, where 109 British troops have lost their lives since 2001. Overall, the U.S-led coalition has lost more troops in Helmand than anywhere else in the country.
Throughout Afghanistan, U.K. and U.S. troops are preparing to leave and are passing control to the local Afghani security forces, with the process estimated to be completed by the end of 2013. U.K. and U.S. troops are to be withdrawn by the end of 2014, the Obama administration has said.
Coalition forces assert that the transition period is proceeding, working well and that the nation's takeover by Afghan security forces is in sight and attainable.
U.S. Marine Corps Gen. James Amos, speaking Thursday at the American Enterprise Institute in Washington after a weeklong visit to Afghanistan, said Afghan army troops in Helmand have taken charge of planning and conducting operations against Islamic insurgents.
"We don't write plans anymore for an operation," Amos said. "We only write supporting plans. We are the force that will provide support as needed -- sometimes it is helicopter lift, sometimes it's (reconnaissance) overhead. But we're back-up in case something happens."
In drawing down the U.S. Marine Corps force there, the Marines have deployed only two infantry battalions in Helmand, down from seven battalions in 2012.
Currently, about U.S. 7,000 Marines are deployed in Helmand, alongside roughly 10,000 ISAF soldiers from Great Britain, Jordan, Georgia and Estonia. Afghan national forces there have grown to about 27,000, Amos said.
"We are on track," he said, adding, "You notice I didn't say we are winning or losing. I didn't say, 'This is Nirvana, we've arrived.' What I am saying is... the campaign plan is on track."
Illustrating the tensions underlying relations between ISAF and the Afghan government, Karzai, in London Monday for meetings with British Prime Minister David Cameron and Pakistani President Asif Ali Zardari commented that security in Helmand was better before the arrival of British troops.
He said it is possible that Western forces are being drawn down in Afghanistan because international leaders realized "they were fighting in the wrong place."
He said he expects fighting to diminish once NATO-led ISAF forces withdraw, adding that greatest threat to Afghanistan's future is "foreign" intervention.