At least one rocket landed in Khor Mor gasfield in Iraq's northern city of Sulaymaniyah, a security official in Baghdad told The National.
The gasfield is being developed by the UAE's Dana Gas company.
Sulaymaniyah is one of three provinces that make up the northern Kurdish region. The region's counter-terrorism service confirmed in a statement that one Katyusha rocket had hit the field.
In a disclosure to Abu Dhabi Stock Exchange on Thursday, Dana Gas said, "Two contractor staff were treated for minor injuries related to the blast but have returned to work."
The blast caused no damage and production operations continued normally without interruption, the company said.
The Kurdistan Counter-Terrorism Service said there were no deaths from the attack and that it was not known where the rocket was launched from.
The Baghdad official, who spoke on condition of anonymity, said that the rocket landed in an open area.
No group has claimed responsibility for the attack.
Dana Gas said it was "co-operating with local security services who are conducting a full investigation" and that the Kurdistan Regional Government (KRG) had "enhanced measures and security forces in the area".
The Khor Mor gasfield is one of major operating fields in Iraq.
In 2007, Dana Gas and Crescent Petroleum signed an agreement with the KRG to appraise, develop, produce, market and sell hydrocarbons from Khor Mor and nearby Chemchemal fields.
For that, they established the Kurdistan Gas Project, which was later joined by the companies OMV, MOL and RWE.
Production started in 2008, sending gas to power stations in the cities of Chemchemal, Bazian and Erbil.
To date, all of the gas produced by the field has been used for in-country power generation, providing fuel for more than 80 per cent of the Kurdistan region.
Dana Gas said that production rose by 50 per cent in 2018 from 305 million standard cubic feet per day to 452 million by the end of 2021, together with 15,000 barrels per day of condensate and more than 1,000 tonnes of liquefied petroleum gas.