Two Brussels brothers who were known to police are among the suicide bombers who carried out deadly terrorist attacks on the international airport and subway in the Belgian capital, local media reported Wednesday.
Khalid and Brahim El Bakraoui had been involved in organized crime, but had so far not been linked to terrorist activities, the broadcaster RTBF said, quoting unnamed police sources.
It said that the two brothers were among the suicide bombers at the Brussels airport on Tuesday, but the broadcaster VRT reported that only one is suspected of having been at the airport, while the other targeted the Maelbeek subway station.
The attacks are believed to have killed some 31 people, while nearly 260 were injured, Health Minister Maggie De Block told the broadcaster Radio 1. Those figures could still change, she added.
The Islamic State jihadist group has claimed responsibility for both attacks in Brussels.
Khalid El Bakraoui had used a false identity to rent an apartment in the Brussels neighbourhood of Forest where a shootout with police occurred during a terrorism raid last week, RTBF said. That incident later led to the arrest of Paris attack suspect Salah Abdeslam.
The 27-year-old El Bakraoui is also thought to have rented a hideout in the southern city of Charleroi that was used to prepare the deadly terrorist attacks in Paris last November, the broadcaster said.
He had been sentenced in early 2011 to five years in prison for carjackings, after having been arrested in possession of Kalashnikov rifles, according to the Belga news agency.
His brother, 30-year-old Brahim, had been sentenced in 2010 to nine years in prison for having shot at police with a Kalashnikov rifle during a hold-up, Belga said.
RTBF reported that another Brussels airport suspect whom police have been looking for since Tuesday may be Najim Laachraoui, an accomplice of Abdeslam who had been sought for months in connection with the Paris attacks.
The suspect, caught on camera with two other men ahead of the airport attacks, had planted a bomb but the device did not explode, Belgian Interior Minister Jan Jambon said.
Belgian prosecutors believe his two companions blew themselves up at the airport departure hall. It was "lucky" that the third bomb did not explode, Jambon told US broadcaster CNN.
The suspect who had been transporting the third bomb ran away, the Belga news agency reported.
The three suspects arrived at the airport by taxi, the mayor of the nearby town of Zaventem told Belga. The taxi driver gave police the address where he picked up the three men, according to the broadcaster VTM.
An emergency meeting of European ministers responsible for security could be convened as early as Thursday on Belgium's request, Dutch Security and Justice Minister Ard van der Steur said on Twitter.
The airport, Belgium's hub for international flights, remained closed on Wednesday.
"As soon as we have access to the terminal building, we can assess the damage. Later today we will assess when operations can be resumed," the airport wrote on its Twitter account.
Belgium, meanwhile, was holding three days of national mourning. Brussels authorities have called for a minute of silence to be held in the city at 12 pm (1100 GMT). The public has been laying out flowers and candles in a central Brussels square since Tuesday.