Updated

Residents of some Kurdish towns and cities in Iran have gone on strike over the last two days to protest last weekend's hangings of four Kurdish dissidents along with another Iranian dissident in Tehran's Evin prison.

Shops have been shuttered and the Kurdish capital is reportedly a ghost town. An Iranian source, who has asked not to be identified, tells Fox News the strike is bold and highly significant, as people who strike in Iran face threats and prosecution. Strikes are "the biggest weapon the people have," another Iranian contact said.

The five people who were hanged were charged with “Moharebeh” or being an enemy of God. The Iranian government also charged them with terrorist acts, but human rights groups say there was no convincing evidence that they were trying to overthrow the regime.

One of those hanged, Shirin Alamhouli, was convicted of trying to blow up a Revolutionary Guard vehicle. Alamhouli apparently wrote letters from prison saying she had been tortured into making a false confession.

Another of those executed, Farzad Kamangar, a 34-year-old teacher and social worker, had become an international cause celebre, according to Hadi Ghaemi of the International Campaign for Human Rights in Iran.

Kamangar's crime, according to Ghaemi, was that his brother was accused of being involved in the Kurdish separatist movement in Iraq and Turkey. No credible evidence was presented to support the case against the brother, Ghaemi said, and Kamanger's trial reportedly lasted just seven minutes.

Ghaemi said he believes the sudden executions had to do with a recent surge in international advocacy for their long-running cases, and to intimidate people who might be planning to come out onto the streets on June 12, the anniversary of last year's disputed election that gave President Mahmoud Ahmadinejad a second term.

The hangings, according to Ghaemi, happened in secret, and the families and lawyers of those killed learned about them after reading an account on Fars News. He said the families have been under pressure, the bodies have not been returned and funerals have not been allowed.

In what Iranian contacts have called a rare occurrence, high-ranking members of Iran’s opposition movement, the Green Movement, publicly protested the killings of the five in Tehran over the weekend. Iranians in the capital don’t often comment on issues involving Iran’s different nationalities.

“The real issue here is way beyond the politics of the opposition movement," Ghaemi said. "It’s about the death penalty in Iran.... Iranian civil society is outraged by the implementation of the death penalty and in general many are trying to change these laws that allow for summary killings after questionable trials and evidence.”

Iran has one of the highest per capita rates of execution in the world, and Ghaemi says many Iranians are “disgusted” by this.

Iran is made up of different ethnic minorities. In addition to the Kurds, there are the Baloch, who have their own tense and often bloody relationship with the central government. A Baloch leader in exile said the different ethnic groups in Iran have always felt a certain “minority” solidarity with one another around issues regarding their rights — the right to speak their native languages, the right for some autonomy and greater opportunities — and that the solidarity has grown in the aftermath of last year’s elections and the ensuing turmoil and crackdown. Events like the execution of the Kurds last weekend serve to intensify those feelings, the Baloch leader said.

It is not clear whether the strikes in Kurdish cities will spark similar action elsewhere in Iran. What is clear to Iran-watchers is that this is a quiet, yet very obvious form of protest.