KABUL, Afghanistan — NATO said Sunday that two separate insurgent attacks in southern Afghanistan killed three soldiers on Saturday, raising the toll to eight in one of the deadliest days for the military coalition this year.
The attacks may have signaled the start of what many fear will be a particularly violent fighting season as President Barack Obama looks to start drawing down American troops.
Two bomb blasts in the south killed the three soldiers, NATO said on Sunday. It had announced on Saturday that a suicide bombing by a Taliban sleeper agent killed five service members at a U.S. base in the east.
NATO has not identified the nationalities of any of the dead from Saturday's attacks. The international military coalition typically waits for national authorities to make such announcements. The majority of troops in both the east and south are American, though there are forces from other nations in both regions.
The latest deaths make 23 NATO service members killed so far this month in Afghanistan and 125 killed this year.
Fighting usually increases in Afghanistan as the weather warms and insurgents climb back over the mountainous border with Pakistan. This year, NATO has pushed farther into Taliban strongholds in the south and has said the goal is to hold these areas so that militants cannot re-establish their dominance.
A deterioration in security over the next few months could complicate the Obama administration's plans to start drawing down troops in July. There are currently nearly 100,000 U.S. combat troops in the country.
When Obama committed to sending an additional 30,000 troops to Afghanistan in December 2009, it was with the promise that the surge would be temporary. The idea was that a surge of forces would turn the tide of the war against the Taliban, and then American troops could hand off to Afghans.
The top U.S. commander in Afghanistan, Gen. David Petraeus, has said he will present Obama with various proposals for the drawdown — all of which include a reduction of forces.
But progress has been slow and it's unclear if the United States will be able to reduce a significant number of forces without ceding ground to the insurgency. While Taliban strongholds have given way in the south, violence has increased in formerly peaceful areas of the north.
Petraeus has also said he plans to aggressively go after the enemy this spring and summer, suggesting the fighting may be more intense than in previous years that set record death tolls.
Although the Afghan army has grown significantly, it is still a largely illiterate and untrained group. There have been repeated internal attacks by soldiers or police who have gone over to the Taliban side.
Saturday's suicide attack in eastern Laghman province also killed four Afghan soldiers and an interpreter. The Taliban claimed responsibility for the bombing, and spokesman Zabiullah Mujahid said Sunday that the soldier was a sleeper agent who had been in the army for years and had been in contact with Taliban operatives for "a long time."
He said the soldier had only been at this specific base for one month. Previously, the Taliban had said the soldier had only joined the army a month ago.
Attacks by insurgents wearing Afghan security forces uniforms are not uncommon, but the death toll has risen recently as NATO and Afghan forces work more closely together. Afghanistan's security forces are also ramping up recruitment of Afghan soldiers and police officers so they can take the lead in securing their nation by the end of 2014, adding more than 70,000 police and soldiers last year in an effort to reach 305,000 troop by the end of this year.
Many of the more than 40 countries contributing troops to the U.S.-led effort in Afghanistan are dealing with eroding support for the mission at home as the war drags into its 10th year.
French Defense Minister Gerard Longuet arrived in Afghanistan on Sunday to meet with his nation's troops and Afghan leaders. He met with French troops at the main southern base in Kandahar province, a spokesman said.