Iran blames US
Hosseini condemned the abduction of Sharafi, adding that it holds the US responsible for his life.
"The Islamic Republic of Iran strongly condemns this aggressive act which is in violation of international law."
Lieutenant Colonel Christopher Garver, a US military spokesman in Baghdad, said that no US troops, or Iraqi troops that report to them, were involved in the incident.
"We've checked with our units and it was not an MNF-I [multinational forces – Iraq] unit that participated in that event," Garver said, referring to a special Iraqi force that is directed by the US military.
Snatched from car
One Iraqi official said that Iraqi soldiers in two vehicles had intercepted a car carrying Sharafi at 6pm on Sunday in a predominantly Shia area.
The Iraqi soldiers took Sharafi to another car and sped away.
Iraqi police officers suspected that a kidnapping was taking place and opened fire on the cars, and detained some of the occupants.
Those who were detained were released on Monday.
US supervision
The Iraqi troops were part of an army unit that receives direct orders from the US military, the Iraqi official said, declining to be identified because of the sensitivity of the information.
The White House has authorised US troops in Iraq to kill or capture Iranian agents deemed to be a threat, saying evidence was mounting that Iran was supporting "terrorists" inside Iraq.
The US has accused Iran of being a major supplier of bombs and other weapons used to target US forces. Tehran has denied the charges.
Tensions have flared between the US and Iran over US-led efforts to isolate Iran and force it to abandon its suspected nuclear weapons programme.