KABUL, Afghanistan (AP) -- For the third time in three days, Americans have been the target of an attack in Afghanistan.
Officials say a suicide bomber killed 21 people, including three U.S. soldiers, today at a checkpoint in a packed market in eastern Afghanistan.
The eastern and southern regions of the country continue to be plagued by regular attacks and clashes.
The 18 Afghans who were killed included an interpreter and two police officers. The rest were civilians.
The bombing came a day after militants carried out two attacks in southern Afghanistan, storming a NATO military base and attacking a police checkpoint. An unspecified number of U.S. troops were wounded.
On Monday, three gunmen in Afghan police uniforms killed an American service member and wounded nine others.