Updated

Iran's postelection unrest is a "full-blown human rights crisis," a watchdog group said Sunday, calling on Tehran to free government critics detained during the crackdown.

Thousands of peaceful protesters, including students, lawyers and prominent human rights activists have been detained following the June presidential election. That has made Iran's reaction to political dissent "a human rights disaster," New York-based Human Rights Watch said in its annual report on violations and abuses worldwide.

SLIDESHOW (Warning: GRAPHIC): Photos From the Violent Clashes

Human Rights deputy Middle East director Joe Stork described the "systematic and brutal targeting" of protesters and government critics by security forces. He said it marked "the worst crackdown" in the Islamic Republic in decades, and called on Tehran to release whose who were captured in peaceful protests or otherwise demonstrating their right to free expression.

"Iran's postelection unrest is now a full-blown human rights crisis," Stork said.

He called it "nothing but an attempt to silence voices of dissent."

Iranian officials have acknowledged that at least 30 protesters died as a result of attacks by the riot police and the hard-line militia group, the Basij. Human Rights Watch believes the death toll is much higher.

The chapter on Iran — one of 15 Middle East countries reviewed in the report — was released in Dubai on Sunday along with findings in Iraq, the United Arab Emirates and Bahrain.

In Iraq, human rights conditions remain "particularly poor for the displaced people, religious and ethnic minorities, women and girls and men suspected of homosexual conduct," Samer Muscati, Iraq researcher for Human Rights Watch, told reporters in Dubai.

Civilians remain targets of attacks as the United States starts to withdraw combat forces from Iraq, Muscati said. He mentioned reports of "widespread torture practices" in Iraqi jails as officials struggle to assume responsibility of about 30,000 detainees who currently are in U.S. custody.

Human Rights Watch urged Iraq's government to make sure national elections in March are "free and fair, with full participation of all parties, regardless of their political or sectarian affiliation."

The call comes amid international concern over Prime Minister Nouri al-Maliki's government to ban hundreds of candidates from the ballot because of suspected links to Saddam Hussein's regime.

In the UAE, the human rights situation worsened in 2009, the group said. Migrant workers particularly suffered as the economy — especially in the boomtown of Dubai — dove deep into the red. the report cited tens of thousands of migrant workers who were forced to go home after construction was either halted or canceled.

Some companies have sent home migrant workers on unpaid "leave" as a way to avoid compensation required in their contracts.

Additionally, the report described female domestic workers who remain deprived of wages and food, endure forced confinement and physical or sexual abuse. And it said foreign residents and UAE citizens have been jailed on debt and corruption allegations.

The report also accused UAE and Bahrain authorities of continued harassment of human rights defenders and government critics. It also cited attempts to stifle media that are critical of the official policies in the two Gulf countries.