BAGHDAD (AP) — Drones targeted oil fields in Iraq’s semi-autonomous northern Kurdish region Wednesday, the latest in a series of attacks in recent days that have put several oil facilities out of commission.

Oil prices rose $1 on Thursday after drones struck Iraqi Kurdistan oil fields for a fourth day, pointing to continued risk in the volatile region.

“The drone attacks in Kurdish energy sites grew out of a sequence of drone attacks since 19 June on Kurdish security forces, where Iraqi militias were claiming that Kurdistan was supporting Israeli and US strikes on Iran,” Michael Knights, a senior fellow at The Washington Institute, told MEE.