An Islamic State official with close ties to the leader of the Paris terrorist attacks was killed, a spokesman for the United States-led coalition against the terrorist organization said Tuesday.

Col. Steve Warren, the spokesman for Operation Inherent Resolve, wrote on his verified Twitter account that Charaffe al Mouadan died on Dec. 24. Warren wrote Mouadan, who was based in Syria, had “a direct link” to Adbelhamid Abaaoud, the ringleader of last month’s deadly attacks.

Warren said al Mouadan “was actively planning attacks against the west,” but did not elaborate.

The Islamic State has said it was responsible for executing the Nov. 13 attacks, during which gunmen and suicide bombers killed 130 people at various locations throughout Paris.

Authorities are still searching for accomplices, and several countries have ramped up their military operations in Iraq and Syria in an attempt to shut down the terrorist organization.

Al Mouadan was one of 10 Islamic State leaders that coalition airstrikes killed in the past month, Warren told reporters at a news briefing. He said several of those killed were planning attacks.

“As long as ISIL external attack planners are operating, the U.S. Military will hunt them and kill them,” Warren wrote on his Twitter page, using a different name for the terrorist organization.