International Workers' Day, also known as Labor Day, is in much of the world an annual celebration of workers and their achievements.

In Iran, things are a little different. 

Thousands of workers in different cities in Iran marched peacefully on Labor Day to take back their rights from the Iranian authorities.  In Tehran, the capital of Iran, workers gathered in front of the Parliament by the thousands and then began marching to protest.

Their theme was labor, all right, but not what the ruling mullahs would have liked.  They chanted: "Detained workers must be released"; "Bread, housing and freedom is our absolute right"; "Astronomical salaries and public misery"; "Social security is our absolute right"; and "Worker, teacher, student let's unite."

The workers carried a placards carrying writing such as "Workers have no food to eat yet," "Billionaire minister! I have not bought meat for 40 months."

The workers gathered in front of the Majlis, or parliament, in Tehran, and were attacked by police and government security forces.  A number of the protesters were arrested.  Meanwhile, a large crowd of workers in Tehran rallied and chanted: "Death to the oppressor, hail to the workers."

In the midst of tight suppression brought down on the demonstrators by the security forces in Tehran, one lady read out a statement on behalf of the workers in support of their rights and against the mullahs' policies over the workers.

The gathering and rally of workers on International Workers' Day, accompanied by the people of Saghez, in Kurdistan Province west of Iran, was attacked by the repressive forces.  A number of protesters were arrested.

In Isfahan, one of the main cities in Iran, retired workers of the steel company marched to protest their horrible living conditions and poverty.  They directed their anger for it at the Iranian authorities, who are not dealing with these abject conditions.

The Iranian regime's intelligence ministry in the city of Sanandaj summoned a few of the workers' leaders and warned them not to hold the Workers' Day celebration in a bid to stop any demonstration taking place.  It failed.

Last year in Iran, there were more than 2,000 labor-related actions, including strikes, demonstrations, and protests.

In Iran, where the mullahs have their seat of power, workers have absolutely no social security.  This is because no labor law supports them, unlike in democratic countries.  According to officials from the Ministry of Labor in Iran, more than 93% of workers are working as temporary contractors.  It means they do not fall under the labor laws and can simply be expelled from factories.

It is noteworthy that the most important and economically critical manufacturing companies are in the hands of the Revolutionary Guards.  These companies make workers work with maximum pressure and suppression.  But when it comes to the workers asking for their wages, they are immediately expelled, suppressed, and arrested.

Some of this has been noticed in the West, and it helps pressure the mullahs.  New legislation from the U.S. Congress (H.R.4744) was passed, titled "Seeking Justice for the Victims of the 1988 Massacre," and was placed there to hold the Iranian regime accountable for its brutality.

Amnesty International reported that "Iran's prisons remain full of political prisoners and prisoners of conscience, many of whom suffer from lack of adequate medical care."

For workers in Iran, it's an ugly picture.  That is why they are protesting, not celebrating.

Hassan Mahmoudi is a human rights advocate, specializing in political and economic issues relating to Iran and the Middle East.