KABUL, Afghanistan — Two more American troops were killed in Afghanistan today, the military said, extending a spike of bloodshed into a second day and pushing the NATO losses in the country to 23 in just over a week.

The latest deaths came as insurgents step up attacks ahead of a major NATO operation in the Taliban stronghold of Kandahar that Washington hopes will turn the tide of the nearly 9-year-old war.

Monday was the bloodiest day this year for international forces in Afghanistan, when seven American troops, two Australians and a French Legionnaire were killed in five separate insurgent attacks in the south and east of the country. Two civilian contractors training police, an American and a Nepalese, also died in a brazen suicide attack Monday in the southern city of Kandahar.

NATO said two service members were killed today in a makeshift bomb blast in southern Afghanistan, and the U.S. military confirmed they were Americans. They provided no further details.

The deaths took the toll on NATO forces to 23 in June, including 13 Americans, according to a count by The Associated Press.

Half of the Monday deaths — five Americans — were in a single blast in eastern Afghanistan, U.S. spokesman Col. Wayne Shanks said without giving further details. It was a grim reminder the insurgents can strike throughout the country — not simply in the south, which has become the main focus of the U.S. campaign.

Two other U.S. troops were killed in separate attacks Monday in the south — one in a bombing and the other by small arms fire.