Time Warner Cable suffered a major Internet outage yesterday, with nearly 80 percent of the company's subscribers waking up to no Internet service. The company, which is the second largest Internet provider in the country with around 67 million total users, confirmed the outage in a tweet.

According to a company spokesperson, a problem during routine maintenance triggered the outage, affecting TWC's 11.4 million high-speed data subscribers spread across 29 states. The problem started at 4:30 a.m. ET and connectivity was largely restored by 6 a.m. ET.

DownDetector, a website that offers a real time overview of outages based on user submissions, was tracking the TWC outage, showing a heat map of the affected areas.

Although the problem seemed most prevalent on the east coast, complains were pouring in from other parts of the country as well. Coincidentally, the outage occurred just a couple of days after TWC agreed to pay a $1.1 million penalty to the FCC for failing to properly report multiple network outages.

While Internet outages are common, this one may prove costly to TWC, as the company is in the middle of an effort to merge with Comcast in a deal valued at $45.2 billion.

Bloomberg is reporting that Governor Andrew Cuomo has directed the New York State Department of Public Service to investigate the outage as part of its review of the proposed acquisition. “Dependable internet service is a vital link in our daily lives and telecommunications companies have a responsibility to deliver reliable service to their customers”, he said.