Five NATO-led soldiers killed in Afghanistan

(CNN) -- Five NATO-led soldiers were killed in eastern Afghanistan on Friday, military officials said.

Four soldiers and a civilian died in a bombing in Kunar province, and another soldier died in a bombing in Khost province, NATO's International Security Assistance Force said.

The nationalities of the troops were not disclosed. Many of the soldiers fighting in the eastern provinces are Americans.

The warfare in Afghanistan has been heating up in recent months, with Afghan, U.S. and allied forces battling Taliban militants all over the country, particularly in eastern and southern provinces.

Foreign troops in Afghanistan are under two commands -- NATO's ISAF and the U.S.-led coalition.

In May, 17 Americans and six allied troops were killed; in June, 28 Americans and 18 allied troops died; and in July, 20 Americans and 10 allied troops were killed.

A group representing 100 national and international nongovernment organizations in Afghanistan issued a statement Friday expressing "grave concern about the deteriorating security situation in Afghanistan and the serious impact on civilians."

The group, the Agency Coordinating Body for Afghan Relief, said there has been "a surge in the number of civilian casualties caused by all sides, a spread of insecurity to previously stable areas, and increasing attacks on aid agencies and their staff."

The Afghan war has been intensifying around the same time violence has been dropping in Iraq.

The 11 U.S. troops slain in Iraq in July was the lowest monthly total since that conflict began; six of the deaths came during hostile situations, and five were the result of causes not related to battle.

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