KABUL (AFP) - Afghan and international security forces have killed about 60 militants in days of fighting in southern and eastern Afghanistan, the government and the US-led coalition said Saturday. More than 30 were killed in clashes from Wednesday to Friday in the southern province of Kandahar, the US-led coalition said in a statement. Security forces called in close-air support during numerous engagements between militants and troops on patrol, it said. "Afghan National Security Forces and coalition forces killed more than 30 militants during three days of fierce battles in Zamto Valley, Kandahar province, August 13-15," it said. The Afghan interior ministry announced separately that 23 rebel fighters were killed in battles on Friday in the southern province of Helmand. The fighting was in the Nad Ali district, where officials have already reported weeks of fighting with police abandoning some of their posts. The defence ministry said meanwhile that seven militants were killed in fighting on Thursday in the eastern province of Paktia. The battles were in remote parts of Afghanistan and the tolls were impossible to independently verify. Fighting between insurgents and Afghan or international troops has picked up into the Afghan summer, with several battles and military operations said to be underway. Militant attacks " most of them claimed by the Taliban, who were in government between 1996 and 2001 " have meanwhile increased by up to 50 percent in some areas, according to officials. The US-led coalition invaded in 2001 and toppled the Taliban regime because they did not hand over Al-Qaeda leaders after the September 11 attacks on the United States.