Thousands report issues with Verizon services. Discover the details of the recent outage affecting mobile connections.

Telecommunications company Verizon is reportedly experiencing a major nationwide service outage Wednesday. Real-time outage monitoring website Downdetector is reporting that Verizon is experiencing a major service outage.

In short, when you see SOS on your phone, it means you're not connected to a cellular network. "If you see SOS or 'SOS only' in the status bar, your device isn't connected to your cellular network, but you can still make emergency calls through other carrier networks," reads an Apple support page on the feature.

Telecom operator Verizon Communications' network was down for tens of thousands of users in the U.S. on Wednesday, according to outage tracking website Downdetector.com. Verizon said it was aware of the issue and that its engineers are working to identify and solve it.

During the Verizon outage, police warned that contacting 911 could be tricky. Big disruptions can have cascading effects on everyday life.