French newspaper Le Monde and several Belgian news outlets, including broadcaster VRT, have identified the second suicide bomber at Zaventem Airport as Najim Laachraoui.
Laachraoui was named earlier in the week by police as a wanted accomplice of Salah Abdeslam.
Analysts said Laachraoui was believed to be a key bomb maker, and French media said he also played a major role in the terror attacks in Paris.
Lukas De Vos from Belgain broadcaster VRT told Morning Report Laachraoui was involved with the Paris attacks, which showed a clear connection between the two events.
One of two brothers behind the Brussels bombings had been deported from Turkey, but Belgium ignored a warning that the man was a militant.
Turkey says it deported one of two brothers behind the Brussels bombing attack in 2015, and that Belgium ignored its warnings.
Two of the suicide bombers who carried out attacks in Brussels on Tuesday have been named as brothers Khalid and Brahim el-Bakraoui, Belgian nationals.
The federal prosecutor said Brahim was part of the attack at Zaventem airport that killed 11 people. Khalid struck at Maelbeek metro, where 20 people died.
Belgian Health Minister Maggie De Block said this morning (NZT) that 31 people were dead and 300 injured, of which 150 remain in hospital, although Mr De Vos said the number of dead was actually 32.
One brother deported from Turkey
Turkish President Tayyip Erdogan said on Thursday (NZT) that Turkey had deported one of the attackers in the Brussels suicide bombings last year, and Belgium subsequently ignored a warning that the man was a militant.
The President's office has confirmed that man was Brahim el-Bakraoui, he was detained in June and deported in July.
Mr Erdogan said Bakraoui was detained in the southern Turkish province of Gaziantep near the Syrian border and was later deported to the Netherlands. Turkey had also notified Dutch authorities.
"We reported the deportation to the Belgian Embassy in Ankara on 14 July 2015, but he was later set free.
"Belgium ignored our warning that this person is a foreign fighter," Mr Erdogan said.
Mr Erdogan's office confirmed that Bakraoui was deported to the Netherlands. It said he was later released by Belgian authorities as "no links with terrorism" were found. It was not clear when Bakraoui was handed over to Belgian authorities.
The situation overnight
The so-called Islamic State (IS) has said it was behind the attacks.
Belgium is observing three days of national mourning.
The nation held a minute's silence at midday (11:00 GMT) on Wednesday. Belgium's king and queen visited the airport and met some of the 260 injured in hospital.
Federal Prosecutor Frederic Van Leeuw said Brahim el-Bakraoui had been identified as the middle of three men in a CCTV image of the suspects of the airport attack.
The man on the left, Najim Laachraoui, was believed to have died at the airport. The man on the right, wearing the hat, has not been named, and fled the scene. The man in the centre is Ibrahim el-Bakroaoui.
Mr Van Leeuw told reporters that a taxi driver said he had picked up the three men from an address in Brussels, which police later raided and found bomb-making materials including 15 kilos of high explosive.
Brahim el-Bakraoui also left a note saying that people were looking for him everywhere and that if he gave himself up he would end up in a cell, the prosecutor said.
Mr van Leeuw said the two brothers were known to police and had criminal records. They were identified by DNA records.
The RBTF broadcaster, quoting a police source, said that Khalid el-Bakraoui, 27, had used a false name to rent the flat in the Forest area of the Belgian capital where police killed a gunman in a shootout last week.
It was during that raid that police found a fingerprint of Salah Abdeslam, the main suspect in the Paris terror attacks of 13 November.
He was arrested in a raid in Brussels last Friday and is due to appear before a pre-trial court on Wednesday.
Khalid el-Bakraoui appears on the Interpol website. It said he was being sought for terrorist activities.
RTBF said Khalid was jailed in 2011 for carjacking while Brahim, 30, was jailed in October 2010 for firing at police.
The man on the right in the CCTV picture, who is being hunted, had a bag of detonators that were left behind and which were later exploded without harming anyone, Mr Van Leeuw said. No other weapons were found at the airport.
Some Belgian media reported on Wednesday that he was the man arrested in Anderlecht area of the city, but Mr Van Leeuw denied the reports.
The first of the victims to be named was Peruvian Adelma Tapia Ruiz, 37.
She had been at Zaventem airport with her Belgian husband and twin four-year-old daughters, who were unharmed, her brother told Peruvian radio.
Belgian Prime Minister Charles Michel, welcomed French counterpart Manuel Valls to Brussels on Wednesday, and insisted that "Europe's destiny is peace and security".
"We are more determined than ever to act in the face of enemies of democracy," he said.
The country has raised its terrorism alert to the highest level.
It has also announced that the international airport will remain closed until Friday 25 March.
The friendly international football match between Belgium and Portugal, scheduled for 29 March in Brussels, has been cancelled.
- BBC, Reuters