A brigade of 3,500-4,000 extra US troops due in Afghanistan in January will be deployed in the east amid efforts to stop infiltration of militants from Pakistan, the US military said Sunday. The brigade has been approved as part of requested US troop reinforcements for Afghanistan's fight against extremists that could amount to about 20,000 personnel, US military spokesman Colonel Greg Julian told reporters in Kabul. "The first brigade that is coming will go into the (NATO-led) RC-East (Regional Command East) and they are going to move into areas that are currently not covered," Julian said. The area includes about a dozen provinces, many of which are on the border with Pakistan where Taliban, Al-Qaeda and other militants are said to have training camps and safe havens.