Two of the suicide bombers who targeted Brussels Airport and the city's subway system were identified Wednesday as brothers Khalid and Brahim Bakraoui, and Belgian media reported that a third man -- the suspected ISIS bomb-maker behind the attacks, was arrested.
A major Belgian newspaper and television network said police took Najim Laachraoui, the Belgian national suspected of making the bombs for the Nov. 13, 2015, attacks in Paris and yesterday's carnage in Brussels, into custody. Officials did not immediately confirm the reports, which said he was arrested in the southwest Brussels district of Anderlecht.
His arrest, if confirmed, would be a major blow against what appears to have been a deadly ISIS cell in Western Europe. But as worries over the Belgian authorities' ability to tackle the home-grown threat mount, there is also new information to suggest there was a fourth, still-unidentified bomber.
The Bakraoui brothers had a long history of crime and were known to authorities, but had not been linked to terrorism before last week.
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RTBF said Khalid El Bakraoui rented the apartment in the Forest neighborhood of the Belgian capital, using a false identity, that was raided by police last Friday in an operation that led to the arrest of top Paris attacks suspect Salah Abdeslam.
Photos of the brothers were plastered across newspaper front pages in Belgium over the weekend, following the raid in Forest, but it was unclear whether they were being actively sought after that raid. Police arrested several people during the operation who were released without charge within hours, but their identities were not made public.
Belgium's state broadcaster said Khalid El Bkraoui was believed to have been the bomber who blew himself up in a train in a subway tunnel near the Maelbeek station in central Brussels. His brother is thought to have blown himself up at the airport.
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Those reports raised questions over the identity of a third man seen in an image from airport security camera video released Tuesday. Laachraoui and Brahim Bakraoui are thought to be pictured in the screengrab, but there have been no indications yet as to the identity of the other presumed suicide bomber in the airport image.
Khalid was given a five year prison sentence in 2011 for armed robbery and car theft, according to French newpaper Le Monde. Brahim was sentenced to nine years in prison for opening fire on policemen using a Kalashnikov during a burglary in 2010, according to Belgian newspaper DH.
Laachraoui, 25, has been openly sought by the police since Monday and it is believed he may have built the bombs for both the Brussels attacks and the Paris carnage in November.
CBS News correspondent Charlie D'Agata reported that, according to Belgian authorities, Laachraoui's DNA was found on the explosives used in the gun and suicide attacks in Paris, which left 130 people dead. He was already Europe's most-wanted man when he walked into Brussels Airport on Tuesday morning.
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Belgian authorities have not confirmed that Laachraoui was the suspect from the airport image still being sought by police.
The carnage in Paris is believed to have been planned largely in Brussels, where a handful of the attackers lived or had links. That attack was blamed on ISIS, but the attackers were "home-grown" militants, from Europe.
The Islamic State of Iraq and Syria (ISIS) claimed responsibility for the attacks at Brussels Airport and one an hour later on one of the city's metro trains, near the station of Maelbeek. Most of the victims were killed in the train blast. - CBS News