KABUL — A female police sergeant shot and killed a US civilian adviser at police headquarters in Kabul on Monday, Afghan police officials said, breaking a relative lull in the so-called insider killings that have strained the relationship between Americans and Afghans here.

The American victim was identified as Joseph Griffin, 49, of Mansfield, Ga., who had worked for DynCorp International as a police trainer since July 2011, according to a DynCorp spokeswoman, Ashley Burke.