Cellphone carrier AT&T is experiencing a massive outage, as the top carriers are seeing mass reports of service outages, according to data from Downdetector.

At approximately 3:35 a.m. on Thursday, top carriers such as AT&T, T-Mobile, and Verizon began experiencing an abnormally high number of outage reports. The outages reported also affected Mint Mobile, Cricket Wireless, TracFone, U.S. Cellular, Boost Mobile, and other smaller providers. Many smaller carriers share phone towers or are subsidiaries of a larger provider.