Kabul, Afghanistan (CNN) -- The female police officer who killed a U.S. contractor in Kabul on Monday is an Iranian national, an Afghan government official said Tuesday.
Sediq Seddiqi, an Afghan Interior Ministry spokesman, said the Afghan police officer is an Iranian citizen who met her Afghan husband in Iran. After they eventually went to live in Afghanistan, he managed to help her illegally obtain Afghan citizenship.
The United States has long been concerned about Iranian terror-related activity against U.S. targets. But Seddiqi said he doesn't have evidence to link the attacker to militant groups carrying out acts of terror. She was arrested and was questioned, he said.
It was the latest in a number of so-called insider attacks by Afghan soldiers and police officers, or attackers dressed like them. More than 50 people have been killed in Afghanistan in similar attacks this year, which the Afghan government calls acts of terrorism.
Meet Afghanistan's future
A biannual Pentagon report to Congress this month said there's been an overall increase in insider attacks on U.S. or coalition training forces.
Monday's incident marked the first such attack involving a female attacker, said Hagen Messer, a spokesman for NATO's International Security Assistance Force.
The victim was identified as Joseph Griffin, 49, of Mansfield, Georgia, according to DynCorp International, which describes itself as "a global government services provider in support of U.S. national security and foreign policy objectives, delivering support solutions for defense, diplomacy, and international development."
The civilian contractor for the security assistance force was working as an adviser to Afghan police, said Maj. Martyn Crighton, another ISAF spokesman. DynCorp said Griffin had been supporting the Afghan Interior Ministry and Afghan National Police Development Program.
Griffin, a veteran of the U.S. military who had served in U.S.-based law enforcement positions, had supported several of the company's global training and mentoring programs since November 2000. He began his most recent assignment in July 2011, DynCorp said.
"Joe spent his career helping people all over the world, most recently working to help the Afghan people secure a better future," said Steve Gaffney, chairman and chief executive of DynCorp International. "The loss of any team member is tragic, but to have this happen over the holidays makes it seem all the more unfair."