Afghanistan ? British troops pushed into a Taliban stronghold awash with opium poppies Monday, drawing mortar and machine-gun fire, in the latest NATO drive to help the government take control of southern Afghanistan.

NATO said the offensive in the south was the latest installment of Operation Achilles, its biggest-ever anti-Taliban maneuver, which began in March.

As Operation Silicon got under way, the U.S. military reported killing 136 rebels during three days of clashes in the once-stable west, the deadliest fighting in the country since January.

Nearly 1,300 people, mostly militants, have died in violence so far this year, based on figures from Western and Afghan officials.