(CNN)-- An Iranian attack with missiles and drones killed 9 fighters from an Iranian Kurdish group based in neighboring Iraq, according to a group official.

Several Kurdish opposition groups are based in northern Iraq, and Iran has regularly targeted them since the start of the conflict with the United States in late February.

The latest attack struck a base of a group called the "Komala Party of Iranian Kurdistan" in the town of Zrkoyzala, an area that has faced repeated attacks during March, according to Komala.

Iranian attacks with drones and missiles on Iranian Kurdish opposition groups continue almost daily. Dozens of incidents have occurred since the signing of the memorandum of understanding between Iran and the United States in mid-June.

Early in the conflict, US President Donald Trump suggested that Iranian Kurdish groups based in Iraq would participate in ground operations against the Iranian regime.

The president told Reuters in early March: "I think it's great that they want to do that, and I fully support it."

But the plan came to nothing, and in late March, Komala leader Abdullah Muhtadi said in an interview: "We will not send our troops to the slaughter."

Another Komala official told Spanish newspaper El País: "When the (Iranian) government becomes weak, the people of Kurdistan will move forward, and the Komala Party will be with them. But it would be good to get more support from allied forces."