The Brussels attackers used ammonium nitrate bombs, two sources tell NBC News. The explosives were estimated at 44 pounds each.
During a raid on a residence linked to the suspects, officials found other bomb components, the Belgian prosecutor’s office said on Wednesday.
More than 30 pounds of another high explosive known as TATP was found along with 150 liters of acetone and 30 liters of hydrogen peroxide, both chemicals that can be used to make bombs.
At that location, investigators also seized detonators, a suitcase full of nails and screws, plastic tubs, ventilators and glass utensils — all signs the home was being used as a bomb-making factory.
It’s not clear whether the suspects or any associates had specific plans for the rest of the materials found in raid in Schaerbeek, a neighborhood in Brussels.
TATP can be used as a booster charge to ensure a powerful detonation of a fairly stable explosive like an ammonium nitrate bomb. It can be used in a mixture with ammonium nitrate or in compact explosive devices like suicide vests.
The suspects brought three suitcase-style bombs to the Brussels Airport on Tuesday morning. They were captured on security video pushing luggage carts with large black bags through the busy terminal.
They blew up the first two bombs 10 seconds apart, officials said.








