Data-center operator CyrusOne confirmed it is actively addressing a technical issue at its Chicago-area facility, which caused a major trading disruption at the Chicago Mercantile Exchange (CME) on Friday. Teams are working to restore normal operations as quickly as possible.

The outage was triggered by a chiller plant failure that affected multiple cooling units at the data center, halting trading of futures and options across several of the world's most liquid markets, including U.S. stocks and Treasurys.

A CyrusOne spokesperson said, "Our engineering teams, along with specialized mechanical contractors, are on-site working to restore full cooling capacity. We have successfully restarted several chillers at limited capacity and have deployed temporary cooling equipment to supplement our permanent systems."

CME Group added that its BrokerTec EU markets remained open and trading, while all other markets were halted due to the cooling issue.

CyrusOne, which operates dozens of data centers globally, owns the primary electronic-trading hub for CME in Aurora, Illinois, just outside Chicago. The company was acquired in 2022 by KKR and Global Infrastructure Partners in a deal valued at approximately $15 billion.