At least six suicide bombers attacked a joint US-Afghan military base in the eastern Nangarhar province of Afghanistan killing a NATO soldier on Saturday, said officials.NATO's International Security Assistance Force (ISAF) confirmed one casualty in the attack without giving further details.The alliance in a brief statement said, "An International Security Assistance Force service member died following a suicide attack by enemy forces in eastern Afghanistan today." The Nangarhar governor's spokesman, Ahmad Zia Abdulzai, aid one attacker in an explosives-packed vehicle blew himself up at the entrance of the base in Nangarhar province, and five other insurgents were shot as they tried to storm the facility.According to the District Chief, Mualim Mashoom, the attack took place in Shinwar district, a volatile area on the main highway from Kabul to neighboring Pakistan, where many Taliban insurgents seek shelter. He also confirmed killing of six suicide bombers.Director of District Hospital Dr. Gul Rehman said two injured civilians had been evacuated to hospital from the scene.Security situation of Afghanistan has been worsening after the national security force has taken control of overall security of the country as NATO/ISAF forces prepare to leave Afghanistan till end of 2014.