The United States placed Iran's morality police on its sanctions blacklist Thursday following the death in custody of Mahsa Amini, a 22-year-old woman arrested for allegedly wearing her hijab (headscarf) improperly.

The US Treasury said the morality police was "responsible" for Amini's death, which has sparked an outpouring of popular anger, as it announced the sanctions "for abuse and violence against Iranian women and the violation of the rights of peaceful Iranian protestors."

The sanctions move was taken as violent protests erupted across Iran following the death last week of Iranian-Kurdish Amini, who had been arrested by the public morality unit of the national police.

At least 17 people have died in the unrest as women burned their headscarves and protesters denounced the government leadership and restrictions on women. 

"Mahsa Amini was a courageous woman whose death in morality police custody was yet another act of brutality by the Iranian regime's security forces against its own people," said Secretary of the Treasury Janet Yellen.

"We condemn this unconscionable act in the strongest terms and call on the Iranian government to end its violence against women and its ongoing violent crackdown on free expression and assembly," Yellen said in a statement.