Workers at refineries in Abadan and Asaluyeh crucial for Iran's oil and natural gas production protested over the death of Mahsa Amini.
While it remains unclear if other workers will follow, the protests come as demonstrations rage on in cities, towns and villages across Iran over the death of Amini after her arrest by the country's morality police in Tehran.
In Abadan, a city once home to the world's largest oil refinery, videos also showed workers walking off the job. The New York-based Center for Human Rights in Iran cited a statement it said came from the Contractual Oil Workers Protest Organizing Council that called for a strike.
"We declare that now is the time for widespread protests and to prepare ourselves for nationwide and back-breaking strikes," the statement said. "This is the beginning of the road and we will continue our protests together with the entire nation day after day."
