About 7,000 US and Afghan government forces launched an offensive against the Taliban in central and eastern Afghan provinces today, as a blast near Kabul killed three Afghan aid workers.
Operation Mountain Fury is the third offensive launched in recent weeks against a resurgent Taliban who have unleashed the worst phase of Afghan violence since they were ousted in 2001.
"Mountain Fury is just one part of a series of coordinated operations placing continuous pressure on Taliban extremists across multiple regions of the country," the US military said in a statement.
About 10,000 NATO and Afghan troops have in recent weeks mounted a big offensive in the southern province of Kandahar, killing hundreds of militants in the Taliban heartland.
Troops from a separate US-led force have been battling insurgents in the eastern province of Kunar, on the Pakistani border, in a third offensive.
Operation Mountain Fury was aimed at defeating the Taliban in the provinces of Paktika, Khost, and Paktiya, all in the east on the Pakistani border, as well as in neighbouring Ghazni and Logar provinces, the US military said. The offensive involved 3,000 US-led troops and 4,000 Afghans.
In a separate statement, the US military said a US coalition soldier training Afghan troops was killed in an attack on a base near the Pakistani border. Another coalition soldier and an unspecified number of Afghan soldiers were wounded.
The level of violence this year has surprised the government and its Western allies and raised concern about the prospects for a country that had been seen as a success in the war on terrorism.
While international and Afghan troops have been launching offensives in the south and east, militant attacks have also increased in parts of the country previously considered safe, including Kabul and the west.
Earlier today, a blast hit a car on a road just to the south of Kabul, killing three Afghan aid workers and wounding one. There was no immediate claim of responsibility. Police blamed "enemies of Afghanistan", a term the government uses to refer to the Taliban and allied militants.
Just over a week ago, a suicide car-bomber attacked a US military patrol in central Kabul, killing 16 people including two US soldiers.