A mysterious explosion near a refugee camp harboring thousands of displaced Turkish Kurds has killed five members of a Kurdish militia and injured three others amid claims that Turkey was responsible for the alleged attack.

The administrative council for the Makhmour camp, southwest of Erbil, claimed late Wednesday's blast was caused by an airstrike carried out by Turkey. The council, which is believed to have close ties to the outlawed Kurdistan Workers Party (PKK), said, “It is significant that a camp under the protection of the United Nations, located in the middle of Iraqi territory was attacked. The Federal Iraqi State, the Kurdistan Regional Government and the UN will be clearly implicated until they issue convincing explanations on the matter.” But the statement failed to specify by what means Turkey had conducted the alleged aerial attack.

Kurdistan 24, an Iraqi Kurdish media outlet, claimed the camp had been struck by a rocket but also did not explain how it may have been launched. Earlier reports suggested the explosion was caused by a car bomb.

Turkey and Iraq have not responded to any of the accusations so far. The United Nations High Commissioner for Refugees, which provides assistance to the camp, has not commented either.