As the authorities in Belgium responded to a series of bomb attacks in Brussels on Tuesday, social networks were quickly flooded with images from witnesses to the immediate aftermath of the deadly explosions at the capital’s main airport and a central metro station.

The first two explosions were reported at Brussels Airport outside the city in Zaventem, where at least 12 people were killed and about 100 were injured.

Witnesses at the airport shared dramatic video and photographs of the smoke-filled terminal, wounded passengers, and the chaotic evacuation following the blasts.

Pinchas Kupferstein, who told the Belgian website Joods Actueel (Jewish News) he had driven to the airport from Antwerp to meet a friend, shot harrowing video of passengers running from the damaged terminal.

More clips of the chaos inside, shared on WhatsApp and other social platforms, were soon picked up and distributed by news organizations, like the Associated Press.

Some of the most distressing images of the aftermath were posted on Facebook by Ketevan Kardava, a Brussels-based correspondent for the national broadcaster of Georgia, the former Soviet republic, and Jef Versele, a Belgian brewer.

One witness, an art director named David Crunelle, also attempted to debunk a rumor that Islamic slogans had been shouted before the explosions at the airport.

About an hour after the attack on the airport, an explosion at the Maelbeek metro station in the city center, near the European Commission headquarters, killed at least 20 people and injured more than 100.

Witnesses shared images of the scene outside the station after that explosion.

Pieter Van Ostaeyen, a researcher who has tracked the role of Belgians fighting in Syria and Iraq for extremist groups like the Nusra Front and the Islamic State, shared what appeared to be a very graphic image of a subway car completely torn apart by the blast.

Soon after, several passengers who had been on other trains close to Maelbeek shared video clips of their frightening evacuation through the darkness of the underground tunnels.