Belgian telecommunications company Telenet opened all of its Wi-Fi hotspots in the country for 24 hours to help facilitate communication in the wake of bombing attacks in the city on Tuesday.

Officials urged residents to avoid making voice calls in the wake of the attacks due to network congestion, asking them to instead use Internet communications or landlines to reach loved ones. Those who made it online were also asked limit their streaming of video or music to avoid overburdening the Internet.

As in previous attacks and disaster situations, the Internet has thus far played a prominent role in management of the crisis after cellular networks quickly became overwhelmed.

Facebook on Tuesday activated its “safety check” feature to help people check on loved ones in the wake of fatal terrorist bombings in Brussels.

The feature, which was also used after the attacks on Paris in November, provides an easy way for Facebook users to tag themselves and let their friends know they’re safe.

The Red Cross also provided an online tool to let residents search for loved ones or list their status as “safe and well.”

Updates about the situation were also being provided by the government on Twitter on Tuesday. Transit updates were also provided on Twitter.

At approximately 8 a.m. Brussels time, two explosions occurred at the Brussels National airport. Those blasts were followed by another explosion in the Maelbeek subway station in the city. Multiple fatalities have been reported. Subway transit in the city has been shut down and traffic to the airport has been rerouted.

The explosions come just days after a raid by Belgian police that resulted in the capture of Paris bombing suspect Salah Abdeslam.

On Tuesday, U.S. wireless carrier AT&T said it will credit wireline and wireless customers for all calls and text messages to Belgium from March 22 through 28.

“Our thoughts are with the people of Belgium and our customers who have friends and family there,” the company said in a statement. “As with any emergency, text messaging is recommended due to the possibility of network congestion in the local area.”

Verizon followed suit on Tuesday, saying it will not charge wireless or wireline customers fo texts or long distance calls from the U.S. to Belgium from March 22-23.

T-Mobile is also offering its Simple Choice postpaid customers free calls and texts to Belgium from March 22-25 via bill credits.

Sprint is waiving fees for texts and calls to Belgium from the United States as well as voice and SMS international roaming fees for those in Belgium for all Sprint, Boost Mobile, Virgin Mobile USA, and Sprint Prepaid customers from March 22-31.

This article has been updated to include communication offers from U.S. wireless carriers.