Belgian authorities have released the names of two of the men who set off bombs that killed 31 and injured 260 in Brussels Tuesday. Ibrahim el-Bakraoui, 30, and Khalid el-Bakraoui, 27, were both Belgian nationals with criminal records, though no known terrorism connections.

The man in the center in the surveillance photograph above is Khalid El-Bakhraoui; he was killed in one suicide blast at the airport. His brother, Ibrahim, died setting off a bomb at the Maelbeek subway station in downtown Brussels shortly afterward. A third suspect, the man on the left in the photograph, has not been identified, but he is believed to be the other airport suicide bomber.

The fourth suspect, the man on the right in the light-colored jacket, remains at large and unidentified at this point. He fled the airport without setting off his bomb. His bag contained nails and explosives, and was recovered at the scene by police.

The two brothers were identified using fingerprints. A taxi driver also came forward, telling police that he picked up three men who all had heavy bags and drove them to the airport. "Perhaps, I had two or three terrorists in my taxi," the driver told police. "I need to tell somebody.”

The three men tried to pack a fourth bag, but it was too heavy to get into the taxi. That bag contained the most explosives, according to the Belgian prosecutor Frederic Van Leeuw's statement at a press conference Wednesday.

The taxi driver led police to where he had picked the men up earlier. There, they discovered a laptop in a garbage that contained a note from Ibrahim El-Bakhraoui. It said, “I don’t know what to do, I am in a hurry. I am on the run. People are looking for me everywhere. And if I give myself up, I will end up in a cell.”

Authorities continue to search for the two remaining suspects and have asked the public for any additional information that may help.

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