Time Warner Cable experienced a massive network outage today (Aug. 27) that shut down Internet services for almost two hours.

The outage was caused by routine network maintenance. It affected 2 percent of the routed networks in the U.S., according to Renesys, a U.S. firm that tracks global internet activity.

The second-largest U.S. cable operator said it doesn't know how many customers lost internet service or cable television service.

Time Warner Cable provides Internet services to about 11 million customers nationwide, according to Reuters.

Spokesman Bobby Amirshahi said the outage occurred at approximately 4:30 a.m. EDT, with services "largely restored" at around 6 a.m. EDT.

Most TWC customers were back online by around 8 a.m. EDT, Amirshahi said.

"During our routine network maintenance, an issue with our Internet backbone created disruption with our Internet and On Demand services," he said, according to Reuters.

The incident came a day after the company agreed to pay $1.1 million to U.S. regulators who found that the company didn't file all the proper paperwork to report multiple network outages in 2013.

The Federal Communications Commission is currently looking over a proposed $45 billion merger between Time Warner Cable and Comcast, considered the two largest cable providers in the U.S.

See Now: OnePlus 6: How Different Will It Be From OnePlus 5?