Kabul, Dec 26 : The female police officer who killed a U. S. contractor in Kabul on Monday is an Iranian national, according to an Afghan government official. Afghan Interior Ministry spokesman, Sediq Seddiqi, said the Afghan police officer is an Iranian citizen who met her Afghan husband in Iran.

They eventually went to live in Afghanistan, where he managed to help her illegally obtain Afghan citizenship, reports CNN. The US 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 added. 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.

A biannual Pentagon report to Congress this month said there has been an overall increase in insider attacks on U. S. or coalition training forces. A spokesman for NATO''s International Security Assistance Force, Hagen Messer said Monday''s incident marked the first such attack involving a female attacker.

The victim, identified as Joseph Griffin, 49, of Mansfield, Georgia, is said to be a veteran of the U. S. military who had served in U. S.-based law enforcement positions. He began his most recent assignment in July 2011. (ANI)