Attack on Afghan aspy chief a cowardly act of terror: US

"We join Afghanistan in condemning this attack that injured the head of National Directorate of Security, Asadullah Khalid," State Department spokesman Mark Toner old reporters.

"We stand strong with Afghanistan against these cowardly acts of terror. We stand strong against this kind of terror and continue to work with Afghanistan to address both the security challenges but also the other challenges that they face," Toner said in response to a question.

The Taliban has claimed responsibility of the attack.