Tehran, Iran ? Iran has released all but three of 31 jailed women’s rights activists, ordering them not to attend a protest to mark International Women’s Day in front of the Iranian parliament, one of the women’s lawyers said Thursday.

Hadi Ghaemi, Iran researcher at Human Rights Watch, said the three women still detained are in solitary confinement and have been on a hunger strike since Tuesday.

Human Rights Watch and Amnesty International accused the Iranian government of increasing persecution of women’s rights advocates and called on authorities to release the last three women.

Human Rights Watch said the arrests took “Iran’s repression of peaceful activists to a new level.”

“We’re calling on Iran to respect the women’s campaign to bring social and legal equality between men and women in Iran,” Ghaemi said.

Security forces arrested the women as they protested the prosecution of five women who are on trial for staging an allegedly illegal demonstration in Tehran in June 2006. The five were among 200 women who demonstrated for legal equality and the nullification of a law that allows Iranian men to have four wives.

The U.S. State Department Thursday said it was deeply disturbed by the reports. “These repressive actions by the regime highlight an alarming trend of intolerance toward the expression of independent views by the Iranian people,” spokesman Sean McCormack said.

Lawyer Mohammad Ali Dadkhah said the women released were ordered not to attend a protest scheduled in front of the Iranian parliament to mark International Women’s Day.

The protest did not materialize, although several hundred teachers demonstrated peacefully outside parliament, calling for higher wages. Police did not intervene.

Dadkhah, who represents two of the freed women, said most were freed on bail of between $11,000 and $55,000.

It was not clear why three women continue to be held. Calls to judicial officials were not returned Thursday, the beginning of the weekend in Iran.

Dadkhah criticized the arrests, saying “they had no logical justification” because the women were just taking part in a gathering.