At least one person was killed and two others were injured after their co-worker opened fire inside an oil and gas company facility in southwestern Iran on Saturday morning.

The incident took place at a chemical laboratory of Gachsaran Oil and Gas Production Company (GOGPC), a subsidiary of Iran's second-largest crude oil firm, the National Iranian South Oil Company (NISOC), in Kohgiluyeh and Boyer-Ahmad province.

According to local reports, an employee of the company, who had been suspended, targeted his colleagues, which resulted in the death of one and injury of two others.

The actual motive behind the shooting incident, quite rare in Iran, is still not known.

The provincial governor's office confirmed the incident and said the suspected employee has been arrested by the police and investigations have been launched.

State-run media cited the police commander of Gachsaran county, Arsalan Khademian, as saying that the accused used a shotgun in the incident, causing severe injuries to three of his co-workers, one of whom succumbed upon arrival at the hospital.

He said more details on the incident would be released following police investigations.

Gachsaran county is home to the Gachsaran oil field, the second largest in the country, with around 67 billion barrels of oil-in-place.

The facility where the shooting incident took place on Saturday morning is affiliated with the Gachsaran oil field. (Anadolu Agency)