Afghan and NATO forces are staging a new push to drive Taliban militants out of their stronghold around the southern city of Kandahar.
Officials say Operation Dragon Strike is an air-and-ground phase of an anti-Taliban offensive that has involved weeks of fighting.
NATO spokesman Josef Blotz, a German brigadier general, says Afghan and coalition forces expect tough battles in the coming days. He says the goal of the operation is to destroy Taliban positions around Kandahar and force the militants to leave or to fight and be killed.
There are no reports of casualties among Afghan or NATO forces since the operation began in recent days. But seven U.S. troops have been killed in other incidents in Kandahar province this month.
Clearing the southern region of militants is a key part of the U.S.-led strategy to help Kabul extend its authority over the country.
In other developments, a roadside bomb blast killed a Polish soldier Monday in the eastern Afghan province of Ghazni.
Britain on Monday identified one of three NATO service members killed in bomb attacks on Saturday as a British soldier. It says the soldier was killed when a roadside bomb struck his vehicle in southern Afghanistan's Helmand province.
NATO says it is investigating the killing of an Afghan civilian by a coalition service member Sunday in the eastern province of Laghman. It gave no details of the circumstances of the civilian's death and said it makes every effort to protect civilians in its operations.
Afghan authorities also are searching for a British aid worker and her three Afghan colleagues kidnapped Sunday by militants in eastern Afghanistan's Kunar province.
The four hostages were working for Development Alternatives Inc, a U.S.-based contractor for the U.S. Agency for International Development.
Some information for this report was provided by AP and AFP.